Patent Application
20130203725
Small cell lung cancer (SCLC) accounts for approximately 14% of all lung cancers. In 2004, there were approximately 26,000 new cases in the United States and 51,000 new cases in Europe (Jemal, 2004). The median survival of patients with untreated SCLC is two to four months (Clark, 1998; Glisson, 2003; Davies, 2004). Combination chemotherapy is currently considered standard first-line therapy for SCLC. The most common regimens include platinum (Pt) drugs such as cisplatin or carboplatin and etoposide. Unfortunately, despite the 40-90% response rate to first-line chemotherapy, long-term survival is unusual because patients develop resistance to chemotherapy and relapse (Sundstrom, 2005; Jackman, 2005). Without further, treatment, the overall expected mean survival after disease relapse is two to four months (Huisman, 1999).
At the time of diagnosis, approximately 30% of patients with SCLC will have tumor confined to the ipsilateral chest, mediastinum, and supraclavicular nodes, designated limited disease. Initially 70-90% of these patients will respond to chemotherapy but the recurrence rate is high (75-90%). The median survival time of patients with limited disease ranges from 14 to 20 months with a two-year survival rate of 40%. Even with the addition of radiation therapy to the chest and head, only 6-15% of patients live beyond five years. Patients with more widespread, extensive disease, have an even worse prognosis. Although response rates to initial chemotherapy remain relatively high, i.e., 40-70%, the median survival of 9-11 months is shorter than for patients with limited disease and long-term survival is rare. Fewer than 5% of patients with extensive disease live beyond two years, even with multi-agent, intensive therapy.
Cisplatin, cis-dichlorodiammine platinum (II), the first organoplatinum anticancer drug, was introduced approximately 40 years ago and possesses a wide range of activity against different tumor types and is still widely used in the treatment of various solid tumors in human patients. However, cisplatin also exhibits a number of undesirable side effects, such as kidney damage (nephrotoxicity) and nausea and vomiting. The search for organoplatinum compounds with fewer side effects than cisplatin led to the discovery of carboplatin (cis-diammine-1,1-cyclobutane dicarboxylate platinum (II)), but this compound also exhibits nephrotoxicity and myelotoxicity and is known to cause cumulative dose-related toxicity that results in slow bone marrow recovery. More recently oxaliplatin (trans-1,2-cyclohexanediammine oxalate platinum (II)) was also developed, but this compound possesses significant neurotoxicity, although its nephrotoxicity was reduced relative to carboplatin. Other platinum-containing drugs that are being studied include satraplatin and lobaplatin. In addition to their undesirable side effects, these organoplatinum compounds are not effective against all tumor types and, significantly, tumors can mutate to develop resistance or tolerance to these compounds, resulting in a tumor that can no longer be controlled with these compounds.
Picoplatin or [SP-4-3]-ammine(dichloro)-(2-methylpyridine)platinum(II) (also known as NX 473, ZD0473, or AMD 473) is a new platinum agent that was developed to be effective against platinum-resistant (such as cisplatin-resistant) cell lines, and is intended for the treatment of solid tumors in humans (Raynaud, 1997; Holford, 1998 (both); Rogers, 2002). Like other platinum analogues, picoplatin causes cell death by the formation of covalent cross-links in DNA that interfere with DNA replication and transcription leading to cell death.
Picoplatin and processes for making picoplatin and for using picoplatin in treatment are disclosed and claimed in U.S. Pat. Nos. 5,665,771 (issued Sep. 9, 1997), and 6,518,428 (issued Feb. 11, 2003), and in PCT/GB0102060, filed May 10, 2001, published as WO2001/087313, which are incorporated herein by reference in their entireties.
In Phase I and II second-line studies with picoplatin, responses were seen in several tumor types, including ovarian, prostate cancer, and SCLC. Substantial nephro-, neuro- or ototoxicity have been observed with picoplatin only rarely in animal studies and in Phase I and Phase II trials (Beale, 2003; Treat; 2002; Giaccone, 2002; Gore, 2002).
There is currently no second-line therapy approved by the United States Food and Drug Administration (FDA) for treatment of patients with refractory SCLC. Oral topetecan is indicated for the treatment of relapsed SCLC in patients who responded but who then relapse ≧45 days following cessation of first-line treatment. Patients who are refractory to first-line treatment have an extremely poor prognosis, and there is no approved drug for such patients. The response rate is <10% for any single-agent regimen in refractory patients (Davies, 2004; Murray, 2003; Sundstrom, 2005; NCCN, 2008) The National Comprehensive Cancer Network (NCCN) 2008 guidelines indicate that monotherapy with ifosfamide, paclitaxel, docetaxel, gemcitabine, or topotecan may be used. However, there have been no randomized trials that demonstrate significant response rate or a survival benefit with these agents and their use in this population is often associated with significant drug-related toxicities. There is a high degree of consensus in the published literature that no currently available therapy offers significant benefit to patients who have refractory disease.
Thus, there clearly remains an unmet need for improved chemotherapy for SCLC.
The present invention provides a therapeutic method to treat humans afflicted with SCLC by administering an effective amount of picoplatin thereto, preferably in combination with an additional chemotherapeutic agent and/or palliative care so that their lives are extended and/or progression-free survival (PFS) is increased, e.g., as compared to SCLC patients receiving only palliative care. Picoplatin is an effective first- or second-line therapy for SCLC can extend patient lifespan or PFS, over untreated patients or BSC-only patients in second-line therapy, wherein the patient groups are chemotherapy-naïve or have failed first-line chemotherapy, respectively. In such cases, picoplatin is especially beneficial to patients who cannot or do not receive further adjunct chemotherapy following disease progression as described hereinbelow.
The present invention also provides a method for treating SCLC comprising: administering picoplatin to a human patient afflicted with SCLC, that is non-responsive to first-line therapy (stable or progressive through first-line therapy) or has responded to first-line therapy but then has relapsed/progressed within 90 days, after cessation (i.e., after the last dose) of first-line chemotherapy. Such patients are referred to as described herein below, as afflicted with “refractory” SCLC. The non-responsive patient subset fails to respond in that the SCLC remains stable or progresses through or during initial or “first-line” chemotherapy comprising the administration of other Pt-containing anti-cancer agents such as carboplatin and/or cisplatin, and/or non-Pt-containing agents such as CAV, etoposide or irinotecan (see Table 9 below).
This group also includes the subset of refractory patients who initially respond during initial or “first-line” chemotherapy comprising other such agents and then relapse/progress within 45 days (1.5 mos.) after the end of said treatment, and so are considered to be “early-relapsing” patients. Patients who are non-responsive to first-line therapy or who respond to initial therapy but then relapse or progress within 180 days (3-6 months) can also be treated effectively with picoplatin in accord with the protocols set forth herein. Therefore, the present invention also provides a method of treating small cell lung cancer (SCLC) comprising: (a) selecting a human patient afflicted with SCLC, wherein the patient was non-responsive to first-line therapy, such as one carboplatin or cisplatin, or wherein the SCLC responded to said therapy but relapsed within about 180 days of cessation of said therapy; (b) administering an effective amount of picoplatin and, optionally, a regimen of best supportive care (BSC) to said patient, wherein the lifespan and/or progression free survival (PFS) of the patient administered the picoplatin are extended over that of a patient selected in step (a) who receives only a regimen of BSC.
Patients who initially respond, but then relapse within 90-180 days after the cessation of first-line therapy are considered herein to have SCLC that “90-180 progressive” or to have SCLC that is believed to be more sensitive to first-line therapy.
In an embodiment of the present method, the picoplatin-treated patient does not require or receive third-line chemotherapy, following progression of the SCLC, for a period of time, e.g., for up to about one year from progression of the SCLC, or for at least up to about 60 days from progression of the SCLC.
Patients who respond to initial therapy but relapse following 6 months are generally considered to be sensitive to first-line therapy and are retreated with drugs used in first-line therapy. However, such patients can also be treated with the picoplatin regimens disclosed herein, as can chemotherapy-naïve patients.
The present method can result in control of the SCLC and can extend the life (e.g., the median survival time or MST) in non-responsive or early-relapsing patients over the life of such SCLC patients receiving only a regimen of best supportive care (BSC) after failure of first-line therapy, either without the administration of subsequent, adjunct chemotherapy (third-line therapy) to either patient group, or if both patient groups receive subsequent adjunct chemotherapy (and the results are balanced for receipt of third-line therapy).
Picoplatin second-line therapy is especially preferred for patients who do not receive third-line therapy, either due to patient choice or for whom third-line therapy is contraindicated or otherwise not employed or not an option. For patients in the picoplatin treatment group who are no more than, or preferably less than 50 years of age, and/or who exhibit an ECOG performance status of 0 or 1 prior to initiation of treatment(s), the present picoplatin treatment(s) are particularly beneficial.
The present method can also be effective to treat SCLC that has metastasized to remote sites, such as to the brain.
“Disease control” is defined as absence of progression, as assessed by a radiological response (complete or partial, “PR”) or stable disease as discussed hereinbelow. The patients treated with picoplatin, and preferably also receiving BSC, can exhibit an extended progression-free survival (PFS) over the group that does not receive active chemotherapy.
Although not intending to be bound by any particular theory, it is believed that there is a shared mechanism of resistance of SCLC to platinum-containing anti-cancer agents cisplatin and carboplatin as well as to certain non-platinum-containing anti-cancer agents such as etoposide and topotecan involving the overexpression of the cellular efflux pump proteins PgP and MRP1 and the cotransport of the drugs with glutathione in a glutathione-dependent process mediated by the enzyme GST-pil. Picoplatin cannot bind to or otherwise combine with glutathione and is therefore not sensitive to the efflux pump transport/resistance mechanism.
Therefore, it is believed that tumors that are nonresponsive to first-line cisplatin and/or carboplatin and/or etoposide or that who respond but relapse soon after cessation of such first-line therapy, remain or may be substantially sensitive to picoplatin. Furthermore, since topotecan shares the same glutathione-dependent resistance mechanism, tumors including SCLC also do not respond or cease responding to topotecan. Resistance to picoplatin may involve other as-yet undefined mechanisms, perhaps operating at the DNA level. Also, this provides a rationale to use picoplatin in first-line as well as second-line therapy in which these drugs are conventionally employed.
For the tumors that have relapsed after showing a response to cisplatin, or carboplatin, with or without etoposide, the resistance can be reversible after a “Platinum-Free Interval” (“PFI”). This has resulted in the recommendation to retreat patients with the same platin after a Platinum-Free Interval greater than 6 months, e.g. of 6-15 months. These tumors may also be sensitive to topotecan if they have responded but relapsed at least 45 days after first-line treatment.
Due to the long-felt and unmet need to provide any effective therapy following failure of first-line therapy, it was unexpectedly found that administration of picoplatin, optionally with a regimen of BSC, to refractory, non-responsive or to early-relapsing SCLC patients after failure of first-line therapy, e.g., with other Pt-containing anti-cancer drugs, provides a benefit to the patient in terms of an extended lifespan, and progression-free survival over that of patients receiving only BSC following failure of first-line therapy. Therefore, an embodiment of the invention provides a method to extend the period of therapy during which platinum-containing drugs may be effectively employed to treat Pt-susceptable tumors by employing picoplatin as second-line therapy as described herein.
It was also unexpectedly found that administration of picoplatin to non-responsive patients or to both non-responsive and early-relapsing patients provided a survival benefit that was greater that attained by administration of picoplatin to patients who were more sensitive, but who relapsed at 91-180 days from cessation of first-line therapy. In other words, this subset of refractory SCLC patients can be helped by treatment with picoplatin, as are patients who are more responsive to first-line therapy, e.g., are initially more sensitive to other Pt-containing anti-cancer agents.
An embodiment of the present invention thus provides a method for treating SCLC comprising (a) selecting a population of human patients who are afflicted with SCLC that failed to respond to initial treatment (remained stable or progressed through, e.g., progressed after two or more cycles of initial treatment) or that responded to initial treatment and wherein the SCLC then progressed within 45 days or 180 days from the last day of the initial treatment, optionally including patients less than 50 years of age and/or who have an ECOG performance score or 0 or 1 vs. 2; (b) administering an effective amount of picoplatin to said patients; and (c) optionally, concomitantly with step (b) providing to the patients a regimen of best supportive care (BSC), so that the life (OS) or PFS of the picoplatin-treated patients is extended. For example, the life or the PFS of the picoplatin-treated patients can be extended over that of SCLC patients having non-responsive or early-relapsing SCLC who do not receive picoplatin or another anti-cancer agent but receive supportive care alone.
Also, said picoplatin-treated patients may not have received additional or adjunct chemotherapy, for a period of time, following disease progression, e.g., for up to about one year or up to about 60 days from progression, as disclosed herein below. Preferably, in trials, OS in the intent-to-treat population is censored at the time such post-study adjunct chemotherapy is initiated. The BSC can also be initiated or be continued for a period of time following picoplatin therapy. Preferably, the present method can also result in disease control of the SCLC.
In an embodiment of the method according to the invention, the picoplatin can be the only chemotherapeutic anti-cancer agent administered to the patient selected for treatment. In another embodiment, picoplatin is administered to said patient in conjunction with an effective amount of at least one non-platinum anticancer agent.
In a further embodiment of the invention, picoplatin is selected as the initial treatment for SCLC, either administered singly, or in combination with other non-Pt containing anti-cancer agents or therapies, including radiation therapy. Such chemotherapeutic agents include docetaxel, paclitaxel, etoposide, irinotecan, pemetrexed, cyclophosphamide, doxorubicin including liposomal doxorubicin (DL), gemcitabine, vincristine and amrubicin.
Due to the unexpectedly long half-life of picoplatin in human plasma and plasma ultrafiltrate after intravenous or oral administration of picoplatin to human subjects, the picoplatin can be administered prior to the adjunct or second anti-cancer agent so as to provide a period during which the patient is exposed to a therapeutically effective anti-cancer amount of picoplatin and a period during which the patient is exposed to a therapeutically-effective anti-cancer amount of picoplatin and the second agent.
For example, after a rapid distribution phase of about one hour, an intravaneous dose of 120 mg/m2 picoplatin was found to exhibit a plasma terminal half-life (t1/2) of about 100-135 hrs. and a plasma ultrafiltrate (PUF) t1/2 of about 60-80 hours. The terminal t1/2 for orally administered solid picoplatin is about 100-200 hr. in plasma. See e.g., International Application Nos. PCT/US10/00735, filed Mar. 11, 2010, PCT/US08/001,752 and PCT/US08/001,746, filed Feb. 8, 2008 which are incorporated by reference herein.
Therefore, picoplatin can be administered intravenously, followed by a gap of up to about 2 days, preferably up to about 1 hr., e.g., about 50 min.±30 min., during which no anti-cancer drug is administered, followed by administration of, e.g., Doxil®, at about 20-60 mg/m2. Following administration of the Doxil® (t1/2=ca. 50 hrs.), the patient can have effective anti-cancer amounts of both picoplatin and Doxil® in their blood until the levels fall below therapeutically-effective anti-cancer levels. Thus, a therapeutically-effective amount of picoplatin can still be present in vivo, after, e.g., the Doxil® concentration has fallen below a therapeutically-effective level. It is believed that this approach will lead to synergistic effects both in anti-cancer efficacy and control or reduction of side-effects (e.g., AEs), due to either agents.
Patients whose SCLC fails to respond to initial treatment as well as those whose SCLC responds to initial treatment and progresses within 45 days of cessation, can advantageously be treated with picoplatin so as to increase their overall survival (lifespan), irrespective of any objective tumor response during picoplatin treatment. In such embodiments, the patients include the subset of those afflicted with SCLC that is highly refractory to the initial previous treatment of the patient (“first-line therapy”) with another platinum-containing drug, such as cisplatin or carboplatin, and/or one or more non-platinum-containing drugs, in that the SCLC does not respond to first-line treatment in that the patient's SCLC remains stable during first-line treatment of at least three cycles (treatment intervals), and until picoplatin treatment, or that progresses during first-line treatment, including SCLC that progresses throughout first-line treatment of at least two cycles (treatment sessions), and continues to progress until initiation of picoplatin treatment.
Picoplatin can be administered in two doses spaced at about 3, 4, 5 or 6 week intervals, preferably at 3 week (21 day) intervals. In one embodiment of the invention, about 60 mg/m2-150 mg/m2, or in a second embodiment, preferably about 150 mg/m2 of picoplatin is administered in each dose. The dose may be administered orally or parenterally, or via combination of oral and parenteral routes. In one embodiment, the picoplatin doses are administered by intravenous infusion of an aqueous solution of picoplatin. The infusion of one dose is typically carried out over about one to two hours. Preferably, the solution is a physiological salt solution that has been previously adjusted to be isotonic with suitable salts. In one embodiment of the invention, about 0.5 mg/ml of picoplatin is present in the aqueous infusion solution, and contains at least one pharmaceutically acceptable tonicity adjuster, such as NaCl, MgCl2, CaCl2, KCl and the like. To achieve the preferred dosing, preferably about 200-300 mg of picoplatin is administered per dose, e.g., per intravenous infusion.
Over the course of treatment of the cancer, 2-15 doses of picoplatin can be administered, with 2-4 doses being typically administered, at intervals of about 21 days (three weeks). Intervals of up to six weeks, e.g., 3-4 weeks, can be employed if, for example, it is necessary to modify the treatment schedule to reduce side-effects.
As used herein, the term “afflicted with SCLC,” is intended to encompass a patient who is afflicted with combined histology SCLC/non-small cell lung cancer, whose cancer has metastasized to sites other than the lung.
As used herein, the term “afflicted with SCLC” also includes patient whose cancer has metastasized to sites other than the lung.
In one embodiment of the present invention a patient afflicted with SCLC, determined to have an absolute neutrophil count of at least 1.5×109/L and a platelet count of at least 100×109/L, a first dose of about 150 mg/m2 picoplatin is administered. If the picoplatin is administered intravenously, it is preferably administered over 1-2 hours. A second dose of 150 mg/m2 picoplatin is administered to said patient about 21 days after the first dose, and further dosing at this level is continued if hematological parameters remain stable.
Best supportive care (BSC) for SCLC comprises a number of palliative treatments that may also have limited therapeutic efficacy against lung cancer, but are not considered to be curative. For example, in one embodiment of the invention, BSC includes one or more, and preferably all, of irradiation to control symptoms of metastatic cancer, administration of analgesics to control pain, management of constipation, and treatment of dyspnea and treatment of anemia, e.g., by transfusions, so as to maintain hemoglobin levels (i.e., ≧9 g/L). Other features of BSC for lung cancer are set forth below. In an embodiment according to the present invention, picoplatin is administered in conjunction with a regimen of best supportive care. In another embodiment, the picoplatin can be the only chemotherapeutic anti-cancer agent administered to the patient. As lung cancer is predominantly a male disease, the patient can be a male patient. As lung cancer is prevalent in Asian countries, e.g., China, Russia, and Central and Eastern Europe, the patent can be selected from ethnic groups representative of these geographic regions. Preferably, the patient presents for picoplatin treatment with ECOG PS of 0 or 1, and/or is less than 50 years of age. The patient may have stable disease or may have progressive disease at the time that picoplatin treatment is begun.
The present method can further comprise administering an effective anti-emetic amount of a 5-HT3 receptor antagonist and dexamethasone to the patient prior to step (c).
The present invention also provides method comprising administering a dosage form adapted for intravenous administration of picoplatin comprising, a solution comprising: (a) water; (b) a tonicity adjuster, such as NaCl, in an amount effective to render the solution isotonic; (c) about 0.5 mg/ml dissolved picoplatin, wherein administration of said dosage form is effective to treat SCLC.
Thus, the present invention also provides a method to use picoplatin to prepare a medicament effective to treat SCLC by administering said medicament, orally or parenterally, to a patient afflicted with SCLC, either as first-line therapy, or as second-line therapy, as said therapy is discussed herein, e.g., in combination with BSC, so that the life of the patient or the PFS of the patient is extended. The medicament can be used singly or with adjunct chemotherapies, as described above.
One embodiment of the invention herein provides a method of treatment and a dosage form suitable for treatment of non-responsive and/or early-relapsing refractory SCLC. For example, if the first-line chemotherapy regimen includes administration of cisplatin or carboplatin, and the tumor is non-responsive to that treatment, in that it remains stable or progresses through initial treatment, or that responds to initial treatment, then recurs within 45 days, such a tumor can be effectively treated with picoplatin as described herein. Non-responsive patients or patients who relapse within 45 days are considered to be in a platinum-free interval following cessation of first-line therapy, in that further treatment with Pt-containing anti-cancer agents other than picoplatin is less effective, e.g., may be wholly ineffective.
Picoplatin is a cytotoxic platinum compound with the chemical name of cis-amminedichloro(2-methylpyridine)platinum(II), or alternatively, [SP-4-3]-ammine(dichloro)-(2-methylpyridine)platinum(II). The name “picoplatin” has been designated as the United States Adopted Name (USAN), the British Approved Name (BAN) and the International Nonproprietary Name (INN) for this product. The molecular formula of picoplatin is C6H10N2Cl2Pt with a molecular weight of 376.14. The structural formula of picoplatin is:
The present invention provides a picoplatin dosage form that comprises a preferably sterile, preferably isotonic, aqueous solution adapted for intravenous (IV) administration. The solution, contains water, picoplatin at a concentration of about 0.3-0.75 mg/mL, e.g., about 0.75-1.0 wt. %, or about 0.5 mg/mL and a tonicity adjuster, such as NaCl. Preferably a preservative is not employed in the solution. The density of the solution is 1.005 g/mL.
The inventors herein have recognized that administration of picoplatin, for example by intravenous administration, to the population of patients with SCLC that is unresponsive to first-line organoplatinum therapy, or that responded but then progresses within the 45 day period after cessation of the first-line therapy, would be advantageous in terms of inhibiting further progression of the SCLC and/or in prolonging the patients' lives. SCLC that fails to respond to first-line treatment or responds then progresses within 90 days was referred to in Example 2 as “refractory” SCLC. The subset of refractory SCLC that initially responds to first line therapy and then progresses within 45 days is referred to as “early-relapsing” SCLC. Cancer that initially responds to first line therapy, then progresses during the 91-180 day period can also be referred to as non-refractory SCLC.
The picoplatin can be administered in doses ranging from about 60 mg/m2 up to about 150 mg/m2 per dose, which has been determined to be the maximum tolerated dose for second-line treatment of SCLC, following initial platinum drug therapy. These dosage units refer to the quantity in milligrams per square meter of body surface area.
In another embodiment according to the invention, patients afflicted with SCLC can be treated with picoplatin in conjunction with a regimen of best supportive care (BSC), and BSC can be continued for a period of time after picoplatin therapy has been completed. In an embodiment of the invention, the patients treated with picoplatin and afflicted with progressive disease were not treated with third-line adjunct therapy for up to about one year, e.g., for up to about 60 days from progression. The general guidelines used to provide subjects with BSC are based on the NCCN Guidelines for SCLC and for palliative care (NCCN Palliative Care Guidelines, 2007). In another embodiment, the picoplatin can be the only Pt-containing chemotherapeutic anti-cancer agent administered to the patient selected for treatment, and preferably it is the only anti-cancer agent that is administered to the patient. In a further embodiment, particularly if picoplatin is selected for first-line or initial chemotherapy, it can be used in combination with other non-Pt-containing anti-cancer agents as disclosed, for example, in U.S. patent application Ser. No. 10/276,503, filed Sep. 4, 2003, and incorporated by reference herein. Such agents can include those disclosed as useful in “adjunct chemotherapy,” disclosed herein below.
The invention herein further includes a method of treating SCLC wherein an effective anti-emetic amount of a 5-HT3 receptor antagonist and dexamethasone are administered to the patient prior to administration of the picoplatin, in order to reduce the side effects of nausea and vomiting that can accompany administration of organoplatinum compounds. An example of a 5-HT3 receptor antagonist that can be used according to the invention is ondansetron.
A Phase II study of picoplatin monotherapy for patients collectively afflicted with SCLC who have non-responsive SCLC, or SCLC that responds to first-line therapy but then progresses within 90 days of completing first-line therapy, or 91-180 day progressive disease, as defined herein, was carried out. A cohort of 77 patients, who had measurable disease, including 44 whose SCLC was unresponsive to first-line organoplatinum chemotherapy (cisplatin, carboplatin or oxaliplatin) and 27 whose SCLC recurred within 90 days after cessation of first-line therapy, plus 6 patients with 91-180 day progressive SCLC, were treated with picoplatin at a dosage of 150 mg/m2 given intravenously over a period of 1-2 hours every 21 days. Picoplatin was provided as a sterile isotonic 0.5 mg/mL aqueous solution for IV infusion.
Patients received 1-10 cycles of picoplatin. A median number of dosage cycles of 2, and a mean number of dosage cycles of 3, were administered. Adverse events (AEs) were graded using the NCI CTCAE. The most frequently reported AEs of any severity are shown in Table 2, below. There was no grade 3 or 4 neurotoxicity, ototoxicity, or nephrotoxicity. There were no treatment-related deaths.
Tumor response was assessed every 6 weeks using RECIST criteria. Of 77 patients, three (4%) had partial response (PR), 33 (43%) had stable disease (unconfirmed PR+SD) and 36 (47%) had progressive disease. Disease control rate was 47% in the 77 patients. Median overall survival was 27 weeks (63 of 77 death events; 95% CI=21-33 weeks). The one-year survival rate was 16.9% (95% CI=11-28). Median progression-free survival was 9.1 weeks (71 of 77 progression events; 95% CI=7-12 weeks). Picoplatin monotherapy resulted in median survival that compares favorably with other reported therapeutic options for SCLC and had a reduced toxicity profile.
White blood cell counts (WBC) with differential and platelet counts and hemoglobin are obtained once between Days 11-15 of Cycles 1 and 2 to determine whether or not hematological toxicity has occurred. Subsequent doses for each subject are reduced by 30 mg/m2 increments per cycle, up to two reductions, if toxicity is observed. Picoplatin is delayed up to 21 additional days and the dose reduced, if limits for absolute neutrophil count (ANC) and platelet counts are not met or for any other toxicity. Doses of picoplatin can be delayed in the event of unresolved hematological toxicities as described below. Doses of picoplatin are reduced in the event of hematological toxicity in the previous cycle, increased creatinine, or a change in body weight as described below. Once a subject has received a dose reduction, the dose may not be re-escalated. Subsequent treatments will continue at that level unless the toxicity recurs, in which case a further reduction of 30 mg/m2 of the reduced dose may be made. Up to two dose reductions will be allowed. If an investigator determines that the degree of dose reduction should be greater than what is contained in these guidelines, investigator discretion shall take precedence to protect the safety of the subject. Similarly, if an investigator determines that a dose reduction should be applied earlier than suggested by these guidelines, investigator discretion shall take precedence to protect the safety of the subject.
The following hematological values must be obtained before picoplatin is administered: absolute neutrophil count (ANC) ≧1.5×109/L; and platelet count ≧100×109/L. If these criteria are not met, then laboratory tests should be measured at a minimum of weekly intervals to see if the required laboratory values are reached. In the event of an absolute neutrophil count less than 0.5×109/L or a platelet count less than 25×109/L, hematology values must be monitored at least twice a week until the neutrophil and platelet counts have improved to above these levels.
A maximum of 21 days is allowed for resolution of the events that do not meet the dosing criteria (i.e., to Day 42 of the cycle). Subjects who do not meet the re-dosing criteria by Day 42 (21 days post planned treatment) should be withdrawn from further treatment for reasons of toxicity.
A dose-reduction of 30 mg/m2 is mandatory if any of the following criteria were observed during the previous cycle:
For hematological events: absolute neutrophil count (ANC) <0.5×109/L for at least 5 days; or absolute neutrophil count <1.0×109/L complicated with Grade ≧2 fever; or platelet count <25×109/L; or not reaching a platelet count >100×109/L and absolute neutrophil count >1.5×109/L by Day 21. For non-hematological events (except nausea and vomiting or alopecia): treatment-related Grade 3 toxicity; or any Grade 4 toxicity.
For patients with abnormal serum creatinine, estimated creatinine clearance should be determined. If the calculated creatinine clearance is <60 mL/min, the subject should be monitored to ensure that there is no further deterioration in renal function. If a reduction in creatinine clearance is observed, the dose of picoplatin should be modified according to Table 3. Dose reductions are in the range of 30-60 mg/m2 per administration.
A change in weight of 10% or more from that used in the previous calculation of body surface area requires a recalculation in body surface area and appropriate modification of drug dose.
A Phase III clinical study was carried out to demonstrate median survival superiority of picoplatin monotherapy with best supportive care (BSC) compared to best supportive care alone in non-responsive SCLC patients or in responsive SCLC patients who exhibited progressive disease within 180 days, including refractory and sensitive patients, as defined above.
Radiological documentation of disease prior to first-line therapy must be available so that the disease status at study baseline can be assessed for protocol eligibility and stratification purposes. The investigator determined eligibility by comparison of chest X-ray or computed tomography (CT) scans obtained prior to, during, and following first-line chemotherapy. During screening, baseline CT or magnetic resonance imaging (MRI) scans were performed for tumor assessment.
The baseline chest and abdomen computed tomography (CT) scans, including bone windows, were used by the radiologist or investigator to confirm radiological status of disease, whether there is measurable disease or not, and to determine the extent of disease at study entry including identification of target lesions, if any, for RECIST response evaluations following subsequent CT scan(s). Measurable disease was not required for study entry, but was required of patients in the radiographically evaluable (RE) population in order to enable the assessment of response rate.
The brain was assessed by a head CT or magnetic resonance imaging (MRI) prior to entry to the study. If brain metastases are identified during the screening exam, treatment with cranial radiation is required prior to randomization. Subjects with symptomatic brain metastases must have been treated with radiotherapy before study entry and must be asymptomatic at the time of baseline evaluations.
Protocol eligible subjects must have SCLC that is either non-responsive to first-line chemotherapy, or that initially responded to first-line therapy then relapsed within 90 days of the cessation of first-line therapy, or responded to first-line therapy then progressed within 91 to 180 days of completing first-line, platinum-containing chemotherapy.
For the purposes of patient stratification in the trial, subjects were stratified by response to first-line therapy as follows:
Subjects were stratified within geographic region (Europe, India, or South America) and by ECOG performance status [PS; (0 or 1 vs. 2)], as shown in Table 4.
There was no time restriction from date of progression until study entry. After stratification, subjects were centrally randomized and assigned 2:1 to receive either picoplatin every 3 weeks plus BSC, or BSC alone.
Prior to each treatment cycle, blood counts, serum chemistry values and calculated creatinine clearance were assessed. The initial dose of picoplatin was 150 mg/m2 as a 1-2 hour intravenous infusion on Day 1 of a 21-day cycle.
Subjects who were randomized to the picoplatin plus BSC arm received anti-emetic therapy with a 5-HT3 receptor antagonist and dexamethasone prior to administration of study drug and received antiemetics following study drug administration, as necessary. All subjects received BSC. White blood cell counts (WBC) with differential and platelet counts were obtained once between Days 11-15 of Cycles 1, 2, and 3 and during any cycle in which a dose reduction was required for hematological toxicity. Picoplatin was delayed up to 21 days, and the dose was reduced, if limits for absolute neutrophil count (ANC) and platelet counts were not met or for any other toxicity.
Follow-up CT scans or other assessments of tumor response were performed every 6 weeks, or after every other cycle while receiving picoplatin, until disease progression. Although 6 cycles of picoplatin are recommended, subjects continued to receive picoplatin beyond 6 cycles as long as they tolerated therapy well and do not have progressive disease.
After discontinuation of picoplatin, all subjects continued to receive BSC, and were to be evaluated every 3 weeks until death, study discontinuation, or the end of the study.
Toxicities were graded using the NCI CTCAE v3. Therapy was delayed up to 21 days (Day 42 of the cycle) if protocol-specified limits for absolute neutrophil count (ANC) and/or platelet count were not met or for any other toxicity.
After discontinuation of picoplatin for any reason, subjects may be treated with other chemotherapy at the investigator's discretion and will then be followed for survival
All BSC alone subjects were evaluated every 3 weeks and continued to receive BSC regardless of disease progression, until death, study discontinuation, or the end of the study. At the time of each visit, a physical examination was done and CBC and serum chemistry values were assessed. Follow-up CT scans were performed every 6 weeks, until disease progression. The delivery of BSC throughout the study, including after disease progression, was monitored.
In the event of disease progression, subjects may be treated with other chemotherapy at the investigator's discretion and will then be followed for survival. Subjects randomized to receive BSC alone did not cross over to receive picoplatin therapy.
Subjects must have documented radiographic evidence of SCLC. Patients with either measurable or non-measurable disease may be included in this protocol. CT scans at approximately 6 week intervals were used to monitor disease status.
Measurable disease is the presence of at least 1 measurable lesion. Measurable lesions are those lesions that can be accurately measured in at least 1 dimension with longest dimension ≧20 mm using conventional techniques or ≧10 mm with spiral CT scan. All baseline evaluations were performed as closely as possible to the beginning of treatment and not more than 3 weeks before the beginning of the treatment.
Clinical lesions were only considered measurable when they are superficial (e.g., skin nodules and palpable lymph nodes).
All subjects received treatment with BSC per protocol specified guidelines. This included analgesics, radiation therapy for painful bone metastases, cranial irradiation for brain metastases, radiation for relief of obstructive symptoms from lesions in the chest, nutritional support, and treatment of anemia, dyspnea, infections, paraneoplastic syndromes and anxiety.
The need for BSC interventions was evaluated during visits to the investigator every 3 weeks for all subjects independent of treatment assignment. The general condition of the subjects as well as any AEs was assessed. Lab tests (complete blood count and serum chemistries) were assessed regularly. Prompt palliative interventions to provide BSC for all subjects were prescribed or administered as a result of these evaluations. If a new chemotherapy was introduced, the subject was followed for survival.
Safety was evaluated from the incidence of laboratory and non-laboratory AEs, including SAEs. The severity of all AEs was evaluated according to the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) Grading Scale, version 3.
To be included in the study, subjects must have met all of the following criteria, listed on Table 5 below.
Subjects meeting any of the following criteria were excluded from study participation, as listed on Table 6.
Subjects were to be discontinued from picoplatin for any of the following reasons, listed on Table 7 below.
Discontinuation from Study
Subjects could be discontinued from participation in the study for any of the reasons listed on Table 8 below. When the subject is discontinued from the study BSC is recommended and subjects should be followed for survival.
“Systemic chemotherapy” or “additional chemotherapy” following picoplatin therapy or following a regimen of BSC as referenced in Tables 7 and 8 can also be referred to as “third-line therapy.” Such therapy can include further treatment with drugs used in first-line therapy, including carboplatin and cisplatin. Carboplatin can be used as a single agent, or combined with a second, non-platinum containing agent such as cyclophosphamide (Cy) optionally with adriamycin and/or vincristine and/or epirubicin, a taxane, taxol, irinotecan, lomustine, gemcitabine, vincristine, (e.g., CEV), etoposide (Ep) or any combination thereof. Cisplatin can be used in combination with irinotecan, Cy, lomustine, gemcytabine (Gem), nimoliezumab, Ep, taxane, taxol, navelbine (Nv) and/or Ep. Other chemotherapeutic agents used in third-line therapy include doxorubicin (singly and with Cy and, optionally vincristine (Vn), Nv, FAU, lomustine, and/or methotrexate), irinotecan, lomustine, gefitinib, hydrazine sulfate, methotrexate, taxanes (e.g., docetaxel and/or paclitaxel), irinotecan, topotecan (and other topoisomerase I or II inhibitors), nimotuzumab (e.g., nimotuzumab in combination with cisplatin), cetuximab, gemcytabine (Gem), vinorelbine, optionally in combination with etoposide or Ep alone. The agents provided herein, or any agent useful to treat cancer, can be combined or used alone for therapy, for example, Vn can be administered in combination with adriamycin; cyclophosphamide can be administered in combination with adriamycin and vincristine (CAV); cyclophosphamide can be administered with doxorubicin and Ep (CDE) and optionally lomustine (CCNU & CDE); cyclophosphamide can be administered with epirubicin and vincristine; navelbine can be administered in combination with Ep; or cyclophosphamide can be administered with vincristine.
Such therapies can increase the life expectancy of certain patients beyond that achievable with second-line picoplatin and/or BSC, used without third-line therapy. However, such chemotherapy may be contraindicated in certain patients, or the patient may choose not to receive additional chemotherapy.
All of the patients had received a first-line, platinum-containing therapy consistent with NCCN Guidelines (Table 9).
All of the patients had received cisplatin- and/or carboplatin-based first-line therapies.
Patients with progressive disease must have had at least 2 cycles of first-line therapy to be considered refractory.
Patients with stable disease must have had a least 3 cycles of first-line therapy to be considered refractory.
Subjects were randomized to receive either picoplatin plus BSC or BSC alone using a central 2:1 blocked and stratified randomization scheme. Each subject will be stratified within to the subject's geographic region; by the subject's response to first-line therapy; and by ECOG PS, as described on Table 10 below.
The Demographics and Prior Treatment of the enrolled population is given in Table 11, below:
This was an open-label study with a blinded randomization scheme. All subjects randomized to receive picoplatin plus BSC received 150 mg/m2 of picoplatin on Day 1 of the first 21-day cycle administered over 1-2 hours. Subsequent doses for each subject may be reduced by 30 mg/m2 decrements per cycle for toxicity as specified below. The dose administered must be within 5% of the target dose. If reduced, the picoplatin dose was not subsequently increased for any individual subject.
The starting dose was based on the body surface area (BSA) calculated from the height and weight of the subject at baseline. Body surface area was calculated using the actual weight of the subject to one (1) decimal place. BSA was recorded to two decimal places for calculating dose of study drug. The equation by Mosteller is being used, as follows:
Subsequent cycles used the BSA calculated for the starting dose. If a subject's weight changes by 10% or more, the BSA was recalculated and the dose adjusted accordingly.
Picoplatin was provided as a sterile isotonic 0.5 mg/mL aqueous solution for IV infusion packed in neutral (Type I) glass injection vials with a nominal volume of 200 mL. The vials are sealed with ETFE copolymer-coated chlorinated butyl rubber stoppers and flip-off crimp seals. The weight per mL for the 0.5 mg/mL formulation is 1.005 g.
Picoplatin vials were supplied to the investigational site in individually packed containers to protect the solution from light. The cardboard containers were temperature monitored during shipment to each clinical site. Each vial is intended for single-use only.
The assigned shelf life of picoplatin 0.5 mg/mL in vials is at least 24 months when stored under the conditions defined by the USP of controlled room temperature, 20 to 25° C. USP controlled room temperature conditions allow for temperature excursions that are generally experienced in pharmacies, hospitals and warehouses, between 15° and 30° C. Provided the temperature usually remains within the allowed range, transient deviations from 4° C. to 40° C. are permitted as long as they do not exceed 24 hours in duration. The drug must be protected from light during storage.
Picoplatin was supplied as a ready-to-use formulation. The contents of the vials were transferred to a suitable bag for administration. Compatibility of the formulation with ethylene vinyl acetate (EVA) infusion bags, polyvinyl chloride (PVC) infusion tubing and polypropylene syringes is established when the materials are protected from light. The compatibility of the formulation with typical administration sets has been set as 8 hours in a covered infusion bag.
The product is highly light-sensitive and the bag must be protected from light during preparation and administration. The product should not be exposed to ambient light for more than 1 hour. As with other platinum complexes, contact with aluminum should be avoided.
There is no preservative or bacteriostatic agent present in the picoplatin formulation. Therefore, picoplatin was to be transferred under aseptic conditions. The solution was to be completely used or discarded within 8 hours of removal from the vial.
Although pretreatment hydration is not required, picoplatin is to only be given to subjects who have an adequate balance of fluid and electrolytes.
Picoplatin was administered by peripheral vein or central line. A 1 hour administration for picoplatin was recommended, although this may be extended to 2 hours at the discretion of the physician if clinically indicated (e.g., concern for volume overload). Concurrent administration of intravenous (IV) fluids, (e.g., normal saline), is not required.
All subjects receiving picoplatin received anti-emetic therapy with ondansetron 8 mg IV (or comparable 5-HT3 inhibitor) plus dexamethasone 8 or 12 mg IV or orally (or equivalent corticosteroid) immediately prior to chemotherapy. Subjects should also have received anti-emetic therapy for several days following treatment as needed, which may include oral lorazepam (Ativan®), prochlorperazine (Compazine®) or similar medications, as clinically indicated for breakthrough nausea and/or vomiting. If vomiting is not controlled with these measures, the dose of ondansetron was to be increased for the second cycle. If still not controlled, aprepitant may be added beginning the third cycle.
Although 6 cycles of therapy were recommended, subjects continued treatment cycles for as long as they did not progress and as long as they continued to tolerate therapy. Subjects were removed from treatment in the event of disease progression or unacceptable toxicity.
Doses of picoplatin were to be delayed in the event of unresolved toxicities as described in this section and in Table 12 below.
A maximum of a 21-day delay was allowed for resolution of the events that do not meet the dosing criteria (i.e., to Day 42 of the cycle). Subjects who do not meet the re-dosing criteria by Day 42 (21 days post planned treatment) were to be withdrawn from further treatment with study drug for reasons of toxicity, but should have continued on study receiving BSC.
The dose of picoplatin was to be reduced by 30 mg/m2 decrements in the event of hematological toxicity in the previous cycle, decreased renal function, or significant non-hematological toxicity.
Once a subject has had a dose reduction, the dose must not be re-escalated. Subsequent treatments will continue at that reduced dose level unless the toxicity recurs, in which case a further reduction of 30 mg/m2 of the reduced dose may be made.
The following hematological values were obtained before picoplatin is administered: (a) ANC ≧1.5×109/L; (b) Platelet count ≧100×109/L; and Hemoglobin ≧80 g/L (8.0 g/dL).
If these criteria are not met, then laboratory tests were to be repeated at a minimum of weekly intervals to see if the required laboratory values were reached. In the event of an absolute neutrophil count less than 0.5×109/L or a platelet count less than 25×109/L, hematology values were to be monitored at least three times a week until the neutrophil and platelet counts have risen above these levels.
A maximum of a 21-day delay was allowed for resolution of toxicity (hematological or non-hematological) that did not meet the dosing criteria (i.e., to Day 42 of the cycle). Subjects who did not meet the re-dosing criteria by Day 42 (21 days post planned treatment) were to be withdrawn from further picoplatin treatment for reasons of toxicity, but should continue receiving BSC on study.
A dose-reduction of 30 mg/m2 was mandatory if any of the following criteria listed on Table 13 were observed during the previous cycle.
Picoplatin had an excellent safety profile with respect to potential neurotoxicity and nephrotoxicity. However, subjects given picoplatin were observed for the possible development of these events.
Supportive-care measures and symptomatic treatment for any drug-related toxicity was initiated, if clinically indicated.
Picoplatin was only to be given to subjects who have an adequate balance of fluid and electrolytes. Hypovolemic subjects were to be rehydrated and serum creatinine and BUN levels repeated. If reduced creatinine clearance was observed, dose reduction was required.
Hematological toxicity was to be managed first, with supportive clinical care as appropriate, and secondly, with subsequent dose reductions, as detailed above.
Platelet transfusions were recommended in the event of a platelet count of less than 50×109/L associated with clinical bleeding or a platelet count of less than 10×109/L in the absence of clinical bleeding.
After an episode of severe neutropenia, dose reduction of picoplatin was the primary therapeutic option. Febrile neutropenia is uncommon following picoplatin. Treatment with hematopoietic colony stimulating factors (e.g., G-CSF) is permitted in subjects at high risk for infection-associated complications, as summarized in the NCCN guidelines. If colony stimulating factors are used, the blood count was to be monitored every 3 days and continued only if ANC remains less than 0.5×109/L. Blood transfusions, for all subjects, or erythropoietin, only for subjects randomized to receive picoplatin, can be used for the treatment of anemia.
Concomitant medications that may contribute to bleeding episodes (e.g., acetyl salicylate) were to be avoided, consistent with standard clinical practice.
The following general guidelines were utilized to provide subjects with BSC and are based on the NCCN Guidelines for SCLC and for palliative care, version 2 (2006), as shown on Table 15 below.
The frequency of clinical events that might merit intervention with BSC, as outlined in the categories listed above, was monitored in order to ensure that equally intense and diligent supportive care is provided to all subjects regardless of treatment assignment.
Screening procedures are listed on Table 16 below. All screening procedures were to be completed within 14 days prior to randomization, except as noted.
These evaluations must be completed on Day 1 of Cycle 1 prior to treatment:
Mid-Cycle of Cycles 1, 2, and 3 and any Cycle which Required Dose Reduction
White blood cell count (WBC) with differential, Hgb, and platelet counts was to be obtained once between Days 11-15 of Cycles 1, 2, and 3 and during any cycle in which a dose reduction was required for hematological toxicity.
If the platelet count is <100×109/L or the ANC is <1.5×109/L, then laboratory tests should have been repeated at a minimum of weekly intervals to see if the required laboratory values are reached. In the event of an ANC <0.5×109/L or a platelet count <25×109/L, hematology values were to be monitored at least three times a week until the neutrophil and platelet counts have risen above these levels.
Prior to Each Treatment Cycle from Cycle 2
The evaluations on Table 17 were to take place every 3 weeks. If treatment was delayed because of toxicity, the evaluations were to be done as originally scheduled, i.e., 3 weeks after the last dose of picoplatin. Items 1-7 were then to be repeated at least weekly, including just prior to the next dose of picoplatin. For serum chemistries, only those that were abnormal needed be repeated.
Evaluations for Subjects on BSC Alone Arm and for Subjects Who have Discontinued Picoplatin for any Reason
If a subject decided to discontinue participation in the study, was unable to comply with the protocol, or if a subject started a further chemotherapy regimen, they were considered in survival follow-up. They were to be contacted every month by telephone, unless consent for survival follow-up was specifically withdrawn. During survival follow-up, information was to be collected on any anti-cancer therapy the subject may be receiving and the survival status of the subject was to be documented. Physical exams, lab evaluations, adverse events, concomitant medications and medical procedures were not to be collected on the CRFs, and no further CT scans are required.
Overall survival: was measured from the date of randomization to the date of death from any cause. For each subject who was not known to have died, overall survival duration will be censored at the date the patient was last known to be alive.
Proportion of subjects with an objective response: was measured as the proportion of subjects who achieved radiological evidence of a CR or PR. For this analysis all subjects in the analysis population, who did not meet the criteria as specified by RECIST for a CR or PR will be included as if they did not have a response. The categorization of response used the best overall response recorded from the initiation of study drug. Objective response required a confirmatory exam documenting the response at least 4 weeks later.
Proportion of subjects with disease control: was measured as the proportion of subjects who achieved radiological evidence of a CR, PR, or SD. For this analysis, all subjects in the analysis population, who did not meet the criteria as specified by RECIST for a CR, PR, or SD were included as if they have progressed. Complete response and PR required a confirmatory exam documenting the response at least 4 weeks later. Stable disease was documented by a follow-up CT scan after study entry at a minimum interval of not less than 6 weeks; this did not require a confirmatory exam.
Duration of response: was measured from the date that the subjects first meets the criteria of response to the date that the subjects progressed (radiologically or symptomatically), or until death from any cause. For each subject that was not known to have progressed or died, duration of response was censored at the date that the subjects was last known to be alive and progression-free.
Progression-free survival: was measured from the date of randomization to the date that the subjects progressed (radiologically or symptomatically), or until death from any cause. For each subject that was not known to have progressed or died, PFS was censored at the date that the subjects was last known to be alive and progression free.
Determination of radiographic disease status for continuation of study drug and analyses of response or progression were determined by the investigator(s) and/or local radiologist(s) using RECIST.
The definition of an AE followed the ICH E6: GCP Step 5, Consolidated Guideline 1.5.96, April 1998 edition:
An AE is any untoward medical occurrence which occurred after randomization, and which did not necessarily have a causal relationship with the study drug. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of the study drug, whether or not related to the study drug.
An unexpected AE is any AE that occurred following the administration of study drug for which the specificity or the severity is not consistent with the current Investigator's Brochure.
A laboratory abnormality was to be reported as an AE only if it was associated with clinical sequelae or requires a therapeutic intervention, including a delay in the administration of picoplatin or a reduction in the dose of picoplatin administered.
Investigators or their designees were to follow subjects for AEs from randomization until death, discontinuation from study or until the end of the study. Safety of picoplatin was assessed by comparing the frequency, severity and nature of the AEs between the safety populations of the 2 treatment arms during the “drug safety period.”
Adverse events that occurred during the study will be graded using the NCI CTCAE v3.0. Adverse events not included in the CTCAE were to be graded according to the following table.
Association or relatedness to test agent will be identified as follows:
An SAE is defined as any AE that results in any of outcomes, listed on Table 22 below.
Missing data will be queried. If the data cannot be obtained, conventions for missing data will be pre-specified for all data not used in the analyses of the primary or secondary endpoints. Data will not be imputed for any missing primary or secondary endpoint variables.
Incomplete data resulting from subjects who terminate the study for reasons other than disease progression or death will be censored for the time-to-event analyses. Investigators must use every possible reasonable effort to obtain survival information on all subjects regardless of the reasons for discontinuation from the study. For each subject that is lost to follow-up or not known to have died at the time of data cutoff, overall survival duration will be censored at the date that he/she was last known to be alive.
Intent-to-Treat (ITT) Population included all randomized subjects according to the treatment group to which they were randomized, regardless of whether or not the subject received any study drug.
This population was used for all the efficacy endpoints.
Radiographically-Evaluable (RE) Population included all randomized subjects meeting the following criteria: (a) had measurable disease (using RECIST) at baseline; and (b) had at least one evaluable post-baseline tumor assessment. This population will be used for the secondary response endpoints other than PFS.
Tabular results will be displayed primarily by treatment group. There may be some tables where information is also displayed by region, cycle, or stratification factor(s) within treatment group. Kaplan Meier plots will be prepared for time-to-event analyses.
The primary endpoint is overall survival. The primary analysis of this endpoint was performed on the ITT population. Overall survival was summarized by treatment group using Kaplan Meier methods.
The primary test for differences in overall survival between the 2 treatment arms was evaluated using a 2-sided stratified log-rank test with α=0.05 significance level adjusted for the interim analyses. The test was stratified according to the specified stratification factors: (a) geographic region (Europe vs. India vs. South America); (b) response to prior therapy (refractory vs. progressed within 91 to 180 days); (c) ECOG PS at baseline (0 or 1 vs. 2); and/or (d) ≦50 years of age. Performance of subsets patients who (a) did not respond to first-line therapy, (b) patients who did not response to first-line therapy or responded to first-line therapy and then relapsed within 45 days and (c) patients who did not receive post-study (third-line) chemotherapy were also evaluated.
Additional supportive analyses will include log-rank tests of the stratification factors and Cox proportional hazards regression analysis of overall survival to investigate the effect of the stratification factors on survival. Other prognostic factors may be investigated in an exploratory nature, as deemed appropriate. All supportive analyses will be evaluated using a 2-sided test with α=0.05 significance level.
The analyses of the response endpoints will use the determination of disease response or progression as determined by the investigator and/or local radiologist using RECIST.
The proportion of subjects who achieve an objective response, and the proportion of subjects who achieve disease control will be assessed in the ITT and RE populations. These endpoints will be presented by treatment arm along with 95% confidence intervals. Each proportion will be compared between treatment arms using a Fisher's exact test.
Logistic regression will be used to investigate the effect of the stratification factors on each of these endpoints. Other prognostic factors may be investigated in an exploratory nature, as deemed appropriate.
Duration of response will be assessed in the ITT and RE populations and PFS will be assessed in the ITT population. These time-to-event endpoints will be assessed using the Kaplan-Meier method and the difference between the two treatment arms will be compared using a stratified log-rank test.
All statistical tests will be evaluated with a 2-sided α=0.05.
Safety will primarily be assessed by comparing the frequency, severity, and nature of the AEs between the safety populations of the two treatment arms during the “drug safety period”. Any comparison against baseline will use the measurement immediately preceding the start of study medication (for the picoplatin subjects) or immediately preceding to the date of randomization (for BSC subjects).
Due to inherent differences in the treatment arms (i.e., the BSC arm will not have a first or last dose of study drug) a “drug safety period” has been defined to allow for the evaluation of drug safety over a time period that will be long enough to assess safety and permit reasonable comparisons between the treatment arms. The “drug safety period” is defined as the time from the date of randomization to 30 days after the last date of study drug administration; 7 days after documentation of progressive disease; or Study Week 12 (Day 84), whichever occurs later, unless the subject discontinues from the study prior to this time.
Adverse events will be summarized by preferred term and body system for each treatment group, cycle, and visit. The MedDRA AE dictionary will be used to map all verbatim AEs to preferred terms and body systems. The frequency of AEs experienced by all subjects will be computed by the treatment cycle of event onset and overall for each treatment group. The tabulation will count the number of subjects reporting each preferred term and the total number of subjects reporting at least 1 event per body system. Summary tables will tabulate AEs by relatedness to study drug, maximum severity (toxicity) and treatment cycle of AE onset. In the event that a subject experiences multiple occurrences of the same event, then the event “most related” to study drug or most severe will be used in the analyses.
Serious adverse events, AEs leading to study drug discontinuation, and laboratory AEs will be summarized by subject listing and described by narrative, where appropriate.
Concomitant medication use will be summarized for the safety population by treatment group. This summary will include all medications taken during the drug safety period. The WHODRUG medication dictionary will be used for coding medications.
Study drug exposure will be summarized by treatment cycle and overall. The initiation of study drug will be considered Day 1 of Cycle 1. The day of administration during the next cycle of study drug will be considered Day 1 of Cycle 2, etc. The drug exposure information will include dosing information, length of cycles, and dose intensity. The number of dose delays and dose reductions will be summarized. Descriptive statistics will be used to summarize this information.
Performance status will be assessed and summarized by comparing baseline values to each scheduled visit. Values will be categorized as improved, maintained, or worsened and will be presented using frequency statistics.
Patients received either picoplatin with BSC (n=268) or BSC alone (n=133). In each arm of the trial, about 85% of the patients enrolled had an ECOG PS of 0-1 and about 15% had an ECOG of 2. The number of cycles (treatments) with picoplatin ranged from 1-15 with a median of 3, at a median cycle length (time between treatments) of 21-42 days (median=22). The median dose intensity (mg/m2/21 days) was 120 mg/m2. Post-study chemotherapy was administered to 40% of the BSC-only patients and to 27% of the patients who received BSC plus picoplatin. After progression, 28% vs. 41% of patients received post-study chemotherapy for picoplatin vs. BSC. The most common post-study chemotherapy regimens included CAV, topotecan, paclitaxel, or carboplatin/cisplatin (alone or in combinations).
Disease control (PR+CR+SD) was observed in 48.2% of the picoplatin plus BSC group vs. 27.4% of the BSC-only group. With a hazard ratio (HR) of 0.8, median survival time (MST) for picoplatin vs BSC was 20.57 wks (CI 19-25) vs 19.71 wks (CI 16-24) (p=0.09). However, those refractory patients who never responded or patients who relapsed within 45 days had a significant improvement in MST (2.86 weeks) when treated with picoplatin and BSC vs BSC. The median survival for these patients treated with picoplatin plus BSC was 21.29 wks vs 18.43 wks for BSC-only patients (see
The medium TTP for the patients receiving picoplatin plus BSC was 11.29 wks vs 6.71 wks for patients receiving BSC (see
However, after progression, 28% vs 41% of patients received post study chemotherapy for picoplatin plus BSC treatment vs BSC only. In patients who did not receive post study chemotherapy, MST for picoplatin (n=194) was 18 wks (CI 16-20) and for BSC (n=79) was 14 wks (CI 11-20) (
Adverse events (AEs) for BSC patients were associated with SCLC. On picoplatin, grade 3/4 AEs >10% were thrombocytopenia (44%), anemia (29%), neutropenia (18%), asthenia (11%). Febrile neutropenia occurred in 2 patients (<1%). No hypersensitivity or picoplatin treatment-related deaths due to hematologic toxicity were observed.
Adverse events related to picoplatin administration are summarized on Table 23, below.
Of 266 treated patients only 13 (4.9%) discontinued picoplatin due to adverse events; 10 (3.8%) due to thrombocytopenia; 3 (1.1%) due to anemia; 1 (0.4%) due to pancytopenia, 1 (0.4%) due to increased LDH; and 1 (0.4%) due to encephalopathy.
Picoplatin efficacy was assessed in an orthotopic model of SCLC brain metastasis by Charles River Laboratories, Discovery and Imaging Services, previously known as MIR Preclinical Services, Ann Arbor, Mich. 106 DMS 114 ACLC cells were implanted intracranially in 9-10 week-old female athymic nude mice (outbred nu/nu). Treatment with vehicle or picoplatin (35 mg/kg) began on day 18 at a mean tumor weight of 13 mg with a dosing schedule of Q7DX4. Magnetic resonance imaging (MRI) was used to assess tumor mass and doubling time (Td) twice a week. [18F] fluorothymidine positron emission tomography (FLT PET) was used as an indicator of tumor proliferative index, expressed as the standardized uptake value (SUV), calculated as follows: SUV=(Mean tumor 18F activity (μCi/g)×body weight (g))÷decay-adjusted injected dose (μCi).
An initial time course for PET (24, 48, and 72 h) was performed to determine optimal post-treatment imaging time, and subsequent post-dose PET imaging was performed at the optimal time (24 h). All procedures carried out in this experiment were conducted in compliance with all the laws, regulations and guidelines of the National Institutes of Health (NIH) and with the approval of MIR's Animal Care and Use Committee. Statistical pairwise comparisons of the MRI tumor volume and PET SUV data were performed using the Wilcoxon rank sum test. P values were adjusted using the method of Holm (non-parametric).
In this model of SCLC brain metastasis, a decrease in cell proliferation, an increase in tumor doubling time, and in one animal treatment-related tumor stasis and increase in survival time was observed. Although the observed trend toward reduced tumor burden in the picoplatin treatment group did not reach statistical significance, technical factors may have contributed to the observation of a trend, rather than statistical significance. For logistical reasons, initial MRI tumor volume measurements for the control group were taken a day before that of the picoplatin (24 h) group and animals were subsequently triaged for equal mean tumor volume. It is therefore likely that tumors in the control group were actually larger than those of the picoplatin group at the same timepoint. See
In addition, four mice in the control group were lost after MRI. Three of the four animals lost contained the three largest tumor volumes in the control group, which reduced the mean tumor volume of the control group. In light of these factors, it is believed that observation of picoplatin anti-tumor activity in SCLC growing in the brain is significant.
All references below, and all other documents, patents, and publications referred to herein are incorporated by reference in their entireties.
Davies A, Evans W, Mackay J, et al. Treatment of recurrent small cell lung cancer. Hematology/Oncology Clinics of North America 2004; 18:387-416.
all of which are incorporated by reference herein in their entireties.
This application claims priority to U.S. provisional application Ser. Nos. 61/311,169, filed Mar. 5, 2010; 61/345,442, filed May 17, 2010; 61/345,451, filed May 17, 2010 and 61/346,777, filed May 20, 2010, all of which are incorporated by reference herein.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/US11/27264 | 3/4/2011 | WO | 00 | 2/13/2013 |
| Number | Date | Country | |
|---|---|---|---|
| 61346777 | May 2010 | US | |
| 61345451 | May 2010 | US | |
| 61345442 | May 2010 | US | |
| 61311169 | Mar 2010 | US |
