An open-label clinical trial evaluating safety and pharmacokinetics of two dosing schedules of panitumumab in patients with solid tumors

PURPOSE

This study evaluated safety, pharmacokinetics, and efficacy of 2 dose schedules and 2 infusion times of panitumumab in patients with advanced solid malignancies.

PATIENTS AND METHODS

This phase I multicenter, open-label study sequentially enrolled patients with advanced solid tumors refractory to standard therapy, or for which no standard therapy exists, to receive panitumumab 6 mg/kg every 2 weeks or 9 mg/kg every 3 weeks. Patients receiving panitumumab every 2 weeks received either all infusions over 60 minutes or a 60-minute infusion for the first dose followed by 30-minute infusions if the first infusion was well tolerated. Patients in the every-3-week cohort received 60-minute infusions. Safety outcomes included the incidence of adverse events and antipanitumumab antibody formation. Pharmacokinetic properties were determined. Efficacy endpoints included response rate and duration of response.

RESULTS

Eighty-six patients were enrolled; 84 (98%) received panitumumab. Treatment-related adverse events occurred in 90% of patients. Safety profiles were similar between patients receiving 30-minute (n = 20) and 60-minute (n = 43) infusions every 2 weeks and patients receiving panitumumab every 3 weeks (n = 21). Panitumumab exposure at steady state increased dose proportionally, and peak serum concentrations were similar in patients receiving either 30- or 60-minute infusions every 2 weeks. Objective responses were seen in 4 patients (5%) with colon, rectal, esophageal, and bladder cancers.

CONCLUSION

Similar drug exposures and safety profiles were observed in patients receiving panitumumab 6 mg/kg every 2 weeks with either 30- or 60-minute infusions and antitumor activity was seen in some patients. Exposure increased approximately dose proportionally at steady state.

Results of a phase II trial of cetuximab plus capecitabine/irinotecan as first-line therapy for patients with advanced and/or metastatic colorectal cancer

BACKGROUND

XELIRI (capecitabine/irinotecan) is effective and well tolerated in metastatic colorectal cancer (mCRC). Cetuximab is active in mCRC alone or with chemotherapy. This study evaluated cetuximab plus XELIRI in first-line treatment of mCRC.

PATIENTS AND METHODS

Subjects had histologically confirmed unresectable colorectal adenocarcinoma (with T4 lesions) after preoperative chemoradiation and/or metastases. Treatment was capecitabine 1700 mg/m2 (850 mg/m2 orally twice a day on days 1-14 for 3 weeks), irinotecan 200 mg/m2 intravenously (I.V.) on day 1 every 3 weeks, and weekly cetuximab (initially 400 mg/m2 I.V. [120 minutes], subsequently 250 mg/m2 [30 minutes]).

RESULTS

Baseline characteristics (N = 70): 43 men (61%); median age, 61.5 years; Eastern Cooperative Oncology Group performance status 0/1 = 66%/34%; 94% adenocarcinoma. Previous therapy: surgery (91%), chemotherapy (14%), or radiation therapy (7%). Responses (patients completing > or = 2 cycles): complete response (5.7%), partial response (37.7%), stable disease (43.4%), and progressive disease (PD; 13.2%); 16 patients discontinued early (n = 4 allergic reaction, n = 2 withdrew consent, n = 2 death, and n = 8 other adverse events [AEs]). The overall per-protocol response rate was 43.4% (34% intent to treat [ITT]; disease control rate, 86.8%; 69% ITT). The median time to progression was 8.1 months (range, < 1-27.0 months), and the median time to response was 1.6 months (range, 1.1-8.4 months). The median survival was 20.5 months, and 45.7% of patients remain alive. Of the 38 deaths, 84% were because of PD. No death was treatment related. The most frequent grade 3/4 treatment-related AEs included diarrhea, neutropenia, and nausea/vomiting; 32% of patients required dose reductions. All patients are off the study primarily because of PD (34.3%) or AEs (40.0%).

CONCLUSION

In summary, XELIRI plus cetuximab is a promising regimen that merits further study for first-line mCRC.

A randomized phase IIIB trial of chemotherapy, bevacizumab, and panitumumab compared with chemotherapy and bevacizumab alone for metastatic colorectal cancer

PURPOSE

Panitumumab, a fully human antibody targeting the epidermal growth factor receptor, is active in patients with metastatic colorectal cancer (mCRC). This trial evaluated panitumumab added to bevacizumab and chemotherapy (oxaliplatin- and irinotecan-based) as first-line treatment for mCRC.

PATIENTS AND METHODS

Patients were randomly assigned within each chemotherapy cohort to bevacizumab and chemotherapy with or without panitumumab 6 mg/kg every 2 weeks. The primary end point was progression-free survival (PFS) within the oxaliplatin cohort. Tumor assessments were performed every 12 weeks and reviewed centrally.

RESULTS

A total of 823 and 230 patients were randomly assigned to the oxaliplatin and irinotecan cohorts, respectively. Panitumumab was discontinued after a planned interim analysis of 812 oxaliplatin patients showed worse efficacy in the panitumumab arm. In the final analysis, median PFS was 10.0 and 11.4 months for the panitumumab and control arms, respectively (HR, 1.27; 95% CI, 1.06 to 1.52); median survival was 19.4 months and 24.5 months for the panitumumab and control arms, respectively. Grade 3/4 adverse events in the oxaliplatin cohort (panitumumab v control) included skin toxicity (36% v 1%), diarrhea (24% v 13%), infections (19% v 10%), and pulmonary embolism (6% v 4%). Increased toxicity without evidence of improved efficacy was observed in the panitumumab arm of the irinotecan cohort. KRAS analyses showed adverse outcomes for the panitumumab arm in both wild-type and mutant groups.

CONCLUSION

The addition of panitumumab to bevacizumab and oxaliplatin- or irinotecan-based chemotherapy results in increased toxicity and decreased PFS. These combinations are not recommended for the treatment of mCRC in clinical practice.

A phase I study of TPI 287, a third generation taxane, administered every 21 days in patients with advanced cancer

2569

Background: TPI 287 is a third generation taxane engineered to overcome multi-drug resistance and to bind to mutant tubulin. In preclinical studies, TPI 287 suppressed the growth of multiple human tumor xenografts in nude mice, including xenografts that expressed mdr- 1 and that were resistant to other taxanes. The safety and tolerability of TPI 287 when administered every 21 days was examined in this Phase 1 dose escalation study in patients (pts) with advanced neoplasms. Methods: TPI 287 was administered over 1 hour every 21 days in ascending doses to groups of 3 pts. Treatment cohorts were expanded to 6 pts in the face of dose-limiting toxicity (DLT); pts could remain on study until the development of progressive disease or an intolerable adverse event. DLT was defined as Gr 4 heme toxicity lasting 7 days; febrile neutropenia, Gr 3 thrombocytopenia with bleeding, Gr 3 elevation of transaminases lasting 7 days or any other Gr 3/4 toxicity other than nausea or vomiting. Results: 14 pts (M:F 5:9, median age 58.5, range 49 - 77) were enrolled in 5 dose levels ranging from 56 - 185 mg/m2. Pts’ cancers included colorectal (5 pts), esophageal (2), pancreatic (2), NSCLC (2), breast (2) and ovarian (1). All patients had received prior chemotherapy (median no. prior treatments: 3 (range, 2 - 10). Drug related adverse events included mucositis, vomiting, diarrhea, neutropenia, thrombocytopenia, myalgias and peripheral neuropathy. Only 1 pt. experienced Gr 4 neutropenia. DLT of Gr 3 peripheral sensory neuropathy was observed at a dose of 185 mg/m2. At a dose of 160 mg/m2 no DLT was observed. 1 pt with pancreatic cancer had a confirmed response to TPI 287 that has persisted for 2.5 months and continues as of this writing. PK data reveal that AUC is generally dose linear. At a dose of 126 mg/m2, clearance was 24.7 + 12.2 L/hr/m2 and t1/2 was 10.6 + 7.1 hrs. Conclusions: TPI 287 can be safely administered in a dose of 160 mg/m2 every 21 days. The dose limiting toxicity was Gr 3 peripheral neuropathy. Anti-neoplastic activity was seen in a patient with pancreatic cancer. PK is dose linear and predictable. Several Phase 2 studies of TPI 287 are being planned.

No significant financial relationships to disclose.

Results of a phase II trial of cetuximab + XELIRI as first-line therapy of patients with advanced and/or metastatic colorectal cancer

4094

Background: We have previously shown that capecitabine/irinotecan (XELIRI) is effective and well-tolerated in metastatic colorectal cancer (mCRC). Cetuximab, a monoclonal IgG1 antibody that binds to the extracellular domain of EGFR, is active in mCRC alone or in combination with chemotherapy. This study was designed to evaluate if cetuximab (Erbitux®) added to XELIRI improves outcome in first-line treatment of mCRC. Methods: Subjects had histologically confirmed colorectal adenocarcinoma with T4 lesions that were unresectable after preoperative chemoradiation therapy and/or metastases. The study regimen was capecitabine 1700 mg/m2 (850 mg/m2 PO BID Days 1–14), irinotecan 200 mg/m2 IV Day 1 every 3 weeks, and weekly cetuximab (initial dose 400 mg/m2 IV over 120 minutes, subsequent doses 250 mg/m2 over 30 minutes). Results: Between February and October 2005, 70 subjects enrolled. Baseline characteristics: 43 males (61%), median age 61.5 years, and ECOG PS 0/1= 66%/34%; 94% of subjects had adenocarcinoma. Prior therapy; surgery (91%), chemotherapy (20%), or radiotherapy (7%). Responses (pts >2 cycles) were; CR (4%), PR (36%), SD (40%) and PD (20%); 15 patients failed treatment; (n=4 allergic reaction, n=2 MD request, n=2 withdrew consent, n=2 Grade 4 neutropenia, and n=5 other AEs). The overall response rate was 40% and the disease control rate was 80%. Median duration of response was 8.8 months (range, 2.6–15.1) and median time to response was 2.0 months (range, 1.2–8.3). 64% of patients remain alive; of the 25 deaths, 84% were due to PD. No death was drug related. The most frequent Grade 3 and 4 treatment-related adverse events (AEs) included: diarrhea (25%), neutropenia (18%), nausea/vomiting (12%), rash and dehydration (9%, each), HFS and fatigue (7%), and allergic reaction (6%). 54% of patients required dose reductions. To date, 64 patients (91%) have gone off study, primarily due to PD (39%) or AE (33%); 3 patients remain on treatment. Conclusions: The combination of cetuximab and XELIRI is feasible and tolerable in first line mCRC. Toxicities are expected and manageable with dose reductions/delay. Funded in part by Bristol-Myers Squibb, Plainsboro, NJ.

No significant financial relationships to disclose.

A phase I study of TPI287: A third generation taxane administered weekly in patients with advanced cancer

2575

Background: TPI 287 is an investigational taxane designed to not be a substrate for mdr-1 and to bind to mutant tubulin. In preclinical studies, TPI 287 demonstrated activity against multiple human tumor xenografts in nude mice, including xenografts that expressed mdr-1 and that were resistant to other taxanes. The safety and tolerability of TPI 287 when administered weekly for 3 weeks followed by a 1 week rest (4 week cycle) was examined in this Phase 1 dose escalation study in patients (pts) with advanced neoplasms. Materials and Methods: TPI 287 was administered over 1 hour weekly for 3 weeks followed by 1 week of no treatment. Treatment cohorts consisted of 3 pts and were expanded to 6 pts in the face of dose-limiting toxicity (DLT); pts could remain on study until the development of progressive disease or an intolerable adverse event. DLT was defined as Gr 4 heme toxicity lasting 7 days; febrile neutropenia, Gr 3 thrombocytopenia with bleeding, Gr 3 elevation of transaminases lasting 7 days or any other Gr 3/4 toxicity other than nausea or vomiting. Results: 25 pts (M:F 16:9, median age 60, range 24 - 86) were enrolled in 7 dose levels ranging from 7–185 mg/m2. Pts’ cancers included colorectal (6 pts); NSCLC (2); prostate (2); squamous cell carcinoma (2) and 1 pt each with cervical, breast, ovarian, gastric, pancreatic, bladder endometrial, NSCLC, SCLC, glioblastoma, melanoma, renal cell and hepatocellular carcinoma. All pts but 1 had received prior chemotherapy (median no. prior treatments: 3 (range, 1–7). Drug related adverse events included nausea, vomiting, diarrhea, fatigue, anorexia, rash, anemia and peripheral neuropathy. 1 pt., who was inadvertently treated with inadequate marrow reserve, experienced Gr 4 neutropenia and died of sepsis. DLT of Grade 3 peripheral neuropathy has been observed. PK data to date reveal that AUC is generally dose linear. At a dose of 127.5 mg/m2, clearance was 30.2 + 11.9 L/hr/m2 and t1/2 8.6 + 1.3 hrs. Results are similar with non-compartmental methods and 2-compartment modeling. Conclusions: TPI 287 can be safely administered in doses of up to 127.5 mg/m2 weekly x 3.

No significant financial relationships to disclose.

A phase II study of milataxel: a novel taxane analogue in previously treated patients with advanced colorectal cancer

BACKGROUND

Milataxel is a novel taxane analog, with evidence of enhanced preclinical activity compared to paclitaxel and docetaxel, especially in cell lines that over express P-glycoprotein. Based on preclinical data that milataxel may be active in colorectal cancer (CRC), a phase II study was performed in patients with advanced previously treated CRC.

PATIENTS AND RESULTS

Forty-four eligible patients were entered. Milataxel was administered intravenously every 3 weeks at the dose of 35 mg/m(2). No objective responses were noted, stable disease was seen in three patients. The median time to progression was 1.4 months (95% CI of 1.2-2.4 months). Three subjects developed neutropenic sepsis and two died. The most frequent grade 3/4 adverse events were neutropenia (57%), leukopenia (27%), dehydration (14%), neuropathy (16%), diarrhea (14%) and thrombocytopenia (14%). The pharmacokinetics of milataxel was assessed in five subjects. The mean milataxel elimination half-life was 64 h and the mean area under the plasma concentration-time curve was 1,708 ng h/ml.

CONCLUSIONS

A syndrome of neutropenic sepsis and diarrhea can be life threatening and close surveillance is needed in patients treated with milataxel at the dose of 35 mg/m(2) every 3 weeks. Clinical activity was not demonstrated in patients with advanced previously treated CRC.

Single-agent pemetrexed in patients with advanced and metastatic hepatoma

14064

Background: The incidence of hepatoma is rising in the United States, primarily due to the increase in the prevalence of hepatitis C. Surgical treatments are rarely an option for patients with advanced hepatoma, and while chemotherapy, particularly with doxorubicin-based regimens, has marginally prolonged survival, response rates have been poor with the burden of high toxicity. Pemetrexed, a folate antimetabolite, has demonstrated activity in hepatoma cell lines with a manageable toxicity profile, making it a potentially useful agent in hepatocellular carcinoma. Methods: A multicenter, Phase II study was conducted to assess the response rate and evaluate the toxicity profile of single-agent pemetrexed (ALIMTA) in first-line patients with advanced or metastatic hepatoma. Pemetrexed 600 mg/m2 IV was administered on Day 1 of each 21-day cycle until disease progression (PD). Patients were premedicated with dexamethasone 4 mg PO BID and received daily folic acid 350–1000 μg PO and Vitamin B12 1000 μg IM every 9 weeks. Results: This nonrandomized study employed Simon’s 2-stage design. There were 21 eligible patients enrolled in the first stage, and all 21 patients were enrolled within 4 months of trial opening. Median age was 72 years (range, 44–88), and most patients were white (62%) and male (81%). Ten percent (10%) had an ECOG PS of 2, 48% Stage IV disease, 52% prior surgery, and 33% tumors of unknown histological grade. The plan was to stop accrual if ≤2 responders were observed among the 21 patients. Of the 21 patients, 3 had SD, 2 had early toxicities (renal/liver failure, sepsis), 15 progressed, and 1 was noncompliant. The trial was closed due to lack of response. The most common Grade 3 hematological toxicities were neutropenia 6/21 (28.6%) and thrombocytopenia 3/21 (14.3%). One patient experienced both Grade 3 nausea and vomiting. There were no Grade 4 toxicities. There were 10 on-study deaths: 9 PD and 1 liver failure. None of the deaths were drug-related. The median actual survival was 2.5 months (range, <1–8). Conclusions: While pemetrexed was well tolerated in this patient population, it was not active. Most adverse events were related to disease state, not study treatment. Supported by Eli Lilly and Company, Indianapolis, IN

[Table: see text]

Safety of bevacizumab plus chemotherapy as first-line treatment of patients with metastatic colorectal cancer: Updated results from a large observational registry in the US (BRiTE)

3536

Background: Bevacizumab (BV) prolongs overall survival and progression-free survival when added to standard chemotherapy for patients with metastatic colorectal cancer (mCRC). BRiTE is a large, community-based observational registry of patients with mCRC receiving BV plus first-line chemotherapy. Safety and efficacy information in unselected patients with mCRC are collected. Chemotherapy regimen choice is at the physician’s discretion. Methods: To facilitate and evaluate enrollment of a typical community-based mCRC population, eligibility criteria were minimized. Cohort demographics were consistent with the NCI Surveillance, Epidemiology, and End Results (SEER) database for mCRC. Patients are followed for up to 3 years, and safety data including targeted BV-associated serious adverse events (SAEs) are updated every 3 months (mo). Results are based on descriptive analyses and are not adjusted for propensity of treatment, baseline characteristics, and treatment effects. Results: 1968 patients were enrolled between Feb 2004 and Jun 2005. Median study follow-up was 10 mo by Nov 4, 2005. SAEs were reported in 12.0% of patients including gastrointestinal perforation (GIP) (1.7%), postoperative bleeding/wound healing complications (1.2%), arterial thromboembolic events (ATE) (2.1%), and grade 3–4 bleeding (1.9%). 3.2% of patients discontinued BV due to a BV-related toxicity, most commonly bleeding. For patients with the respective event(s), median time to first event was 2.1 mo for GIP, 3.5 mo for ATE and 4.0 mo for grade 3–4 bleeding. 8.9% of patients with no history of hypertension (HTN) developed HTN requiring medication and 6.2% of patients who had HTN requiring medication at baseline experienced worsening of their HTN while on study treatment. Conclusions: In this unselected population of patients with mCRC, the safety profile of BV plus various chemotherapy regimens appears consistent with that observed in the pivotal BV trial. Overall discontinuation of BV due to a BV-related toxicity was uncommon. In this large community-based observational registry, no new BV associated safety issues have been identified.

[Table: see text]

Risk factors for gastrointestinal perforations in patients with metastatic colorectal cancer receiving bevacizumab plus chemotherapy

3535

Background: Bevacizumab (BV) prolongs overall survival and progression-free survival when added to standard chemotherapy in patients (pts) with metastatic colorectal cancer (mCRC). BRiTE is a large, community-based observational registry of pts with mCRC receiving BV plus first-line chemotherapy (CT). Incidence rate, temporal pattern, and potential risk factors associated with gastrointestinal perforation (GIP) were explored. Methods: Baseline patient characteristics (BC), including prospectively identified potential risk factors for GIP, were collected at study entry. Safety data were collected every 3 months (mo). Logistic regression models, adjusted and unadjusted for treatment assignment, were used to identify BC potentially associated with GIP. Results: 1968 pts were enrolled between Feb 2004 and Jun 2005. Median study follow-up was 10 mo as of Nov 4, 2005. GIPs were observed in 34 pts (1.7%). For pts with GIP, median time to first event was 2.1 mo; the majority of events were non-fatal and occurred within the first 3 mo after starting BV. BC including GI medical history (chronic aspirin or NSAID use, peptic ulcer disease, diverticulosis) were similar in pts with or without GIP and with earlier or later GIP onset (≤ or >3 mo from start of BV). Although adjusted models did not show any significant BC, GIP rates were numerically higher in pts with primary tumor intact (2.6%) vs. resected (1.6%). Furthermore, univariate analyses revealed a significant difference between intact (2.3%) and resected (0.8%) primary tumor for earlier GIP (≤3 mo from start of BV). The majority of pts with GIP had at least one of the following: acute diverticulitis, intra-abdominal abscess, gastrointestinal obstruction, tumor at GIP site, abdominal carcinomatosis, prior abdominal or pelvic radiation therapy. Conclusions: Preliminary analyses indicate the incidence of GIP in this large, community-based observational registry is similar to that previously reported in phase III mCRC trials with BV. No associations between specific BCs and an increased risk of GIP were identified. Patients with primary tumor intact were more likely to incur a GIP within the first 3 mo of starting BV and CT.

[Table: see text]

Results of a phase II trial of cetuximab+XELIRI as first-line therapy of patients with advanced and/or metastatic colorectal cancer

13502

Background: We have previously shown that capecitabine/irinotecan (XELIRI) is effective and well-tolerated in metastatic colorectal cancer (mCRC). Cetuximab targets EGFR and is active in mCRC either alone or combined with chemotherapy. This study evaluated potential improved outcomes with cetuximab+XELIRI in first-line treatment of mCRC. Subjects and Methods: Subjects had histologically confirmed colorectal adenocarcinoma with T4 lesions that were deemed unresectable after preoperative chemoradiation and/or metastatic disease. Treatment: capecitabine 1700 mg/m2 (850 mg/m2 PO BID Days 1–14), irinotecan 200 mg/m2 IV Day 1 every 3 weeks, and weekly cetuximab (initial dose 400 mg/m2 IV over 120 minutes, subsequent doses 250 mg/m2 over 30 minutes). Toxicity was assessed at each visit. Results: Between February and October 2005, 70 subjects enrolled. Baseline characteristics: 43 males (61%), 79% White, median age 61.5 years (range, 32.2 - 85.4), and ECOG PS 0/1= 66%/34%. 63% of subjects had Stage IV disease at diagnosis; 87% of subjects had adenocarcinoma. Prior therapy: surgery (n=60, 86%), chemotherapy (n=14, 20%), and radiotherapy (n=5, 7%). Grade 3–4 treatment-related toxicities in >1 subject included diarrhea (17%); neutropenia and rash (8.5% each); dehydration (7%); nausea/vomiting (5%); and anorexia, dyspepsia, and hypokalemia (3% each). 30 subjects discontinued due to progressive disease (PD) (n=9), toxicity (n=12), MD decision (n=2), patient request/withdrew consent (n=3), death (n=1) and other (n=3; doses delayed >3 weeks). To date 5 subjects have died; no death was treatment-related. Evaluation of tumor responses is ongoing. Conclusions: The combination of cetuximab+XELIRI is feasible and well-tolerated in first-line mCRC. Updated safety and efficacy data will be presented. Funded in part by Bristol-Myers Squibb, Plainsboro, NJ.

[Table: see text]

Efficacy of bevacizumab plus chemotherapy as first-line treatment of patients with metastatic colorectal cancer: Updated results from a large observational registry in the US (BRiTE)

3537

Background: Bevacizumab (BV) prolongs overall survival and progression-free survival (PFS) when added to standard chemotherapy (CT) in patients with metastatic colorectal cancer (mCRC). BRiTE is a large, community-based observational registry of patients with mCRC receiving BV plus first-line CT. Safety and efficacy information in unselected patients with mCRC are collected. Chemotherapy regimen choice is at the physician’s discretion. Methods: 1968 patients receiving BV plus first-line CT were enrolled at 248 sites in 49 states between Feb 2004 and Jun 2005. Patients are followed for up to 3 years, with data reporting every 3 months (mo) including disease status as assessed by investigator using his/her method of choice. Patients were grouped twice by CT. Cox regression models, adjusted and unadjusted for treatment assignment, were used to identify baseline characteristics (BC) and differential chemotherapy effects on PFS. Results: Cohort demographics were consistent with the NCI Surveillance, Epidemiology, and End Results (SEER) database for mCRC. Median study follow-up was 10 months by Nov 4, 2005. CT regimens included FOLFOX (55.8%), FOLFIRI (14.1%), and IFL (9.7%). Based on observed progression events (n=800) or deaths (n=123), projected median PFS is 11.3 mo (95% CI: 10.4–11.7). Median PFS was comparable in patients treated with CT regimen based on irinotecan (11.3 mo), oxaliplatin (11.4 mo), or neither (10.2 mo) (CT Grouping 1); or 5FU infusion (11.5 mo), 5-FU bolus (9.7 mo), or capecitabine (11.6 mo) (CT Grouping 2). Significant BC in adjusted and unadjusted models are ECOG performance status (PS), primary disease site, and albumin, with no significant difference among CT regimens. Conclusions: This large, community-based registry included a patient population with demographics consistent with the SEER database for mCRC. Preliminary median PFS of 11.3 mo compares favorably to that reported in the pivotal trial. Median PFS appears to be comparable for all CTs when combined with BV. Higher baseline albumin, PS of 0, and primary disease site of rectum were associated with improved outcome.

[Table: see text]

A phase II clinical and pharmacokinetic study of intravenous exatecan mesylate (DX-8951f) in patients with untreated metastatic gastric cancer

PURPOSE

To determine the anti-tumor activity DX-8951f when administered as a 30-minute infusion daily for 5 days every 3 weeks to patients with previously untreated metastatic gastric cancer, and to evaluate toxicities and pharmacokinetics (PK) of DX-8951f in this patient population.

PATIENTS AND METHODS

Forty-one patients were enrolled. All had previously untreated metastatic gastric cancer. DX-8951f was administered until disease progression or unacceptable toxicity. Responses were assessed after every 2 courses using RECIST criteria.

RESULTS

Thirty-nine patients were evaluable. Two patients achieved a partial response (PR) and 18 achieved stable disease (SD), including five patients with unconfirmed PR. A total of 141 courses of therapy were delivered (median 3, range 1-10). The most common drug-related toxicity was neutropenia. Non-hematologic toxicities were mostly mild to moderate; the most common were nausea, vomiting and anorexia. Plasma concentrations of DX-8951 (the anhydrous form of DX-8951f) were well described using a linear 2-compartment PK model. All concentrations and dose events were simultaneously modeled and explained by the population PK model. There was no evidence of non-linearity in the elimination PK, auto-inhibition or induction of DX-8951 clearance over the five days of administration.

CONCLUSIONS

DX-8951f had modest activity against metastatic gastric cancer and its PK was dose-proportional. The toxicity profile was predictable and manageable. Further development of this agent is warranted.

An open label trial of sustained-release cytarabine (DepoCyt) for the intrathecal treatment of solid tumor neoplastic meningitis

Drugs currently available for intrathecal administration are cleared rapidly from the CSF. DepoCyt is a slow-release formulation of cytarabine that maintains cytotoxic concentrations of free cytarabine in the CSF for >14 days following a single injection. DepoCyt was administered to 110 patients with a diagnosis of neoplastic meningitis based on either a positive CSF cytology (76) or neurologic and CT or MRI scan findings sufficient to document neoplastic meningitis (34). Patients were treated with DepoCyt 50mg every 2 weeks for 1 month of induction therapy by either lumbar puncture (LP) or intraventricular (IVT) injection. Patients without neurologic progression were candidates to receive an additional 3 months of consolidation therapy. All patients received dexamethasone 4 mg BID on days 1-5 of each cycle. Median time to neurologic progression was 55 days; median overall survival was 95 days. Among the 76 patients with a positive CSF cytology at baseline, 70 were evaluable for response, and of this group 19 (27%) attained the criteria for response (cytologic response in the absence of neurologic progression). The most important adverse events were headache and arachnoiditis. When drug-related, these were largely low grade, transient, and reversible. Drug-related grade 3 headache occurred on 4% of cycles; grade 3 or 4 arachnoiditis occurred on 6% of cycles. No cumulative toxicity was observed. DepoCyt injected once every 2 weeks produced a response-rate comparable to that previously reported for methotrexate given twice a week. The once in every 2-week-dosing interval offers an advantage over conventional schedules (2-3 doses/week) used for other agents available for intrathecal injection.

Phase II study of oral capecitabine in patients with advanced or metastatic pancreatic cancer

PURPOSE

To determine the safety and efficacy of capecitabine (Xeloda; Roche Laboratories, Nutley, NJ) in patients with metastatic or unresectable, locally advanced pancreatic cancer.

PATIENTS AND METHODS

Forty-two patients were treated with oral capecitabine 1,250 mg/m(2) administered twice daily (2,500 mg/m(2)/d) as intermittent therapy in 3-week cycles consisting of 2 weeks of treatment followed by 1 week without treatment. Tumor lesions were assessed by computed tomography scan or physical examination at 6-week intervals (after every two cycles). Adverse events were monitored continuously during treatment and for 28 days after the last dose of study drug.

RESULTS

Ten (24%) of 42 patients experienced a clinical benefit response (95% confidence interval [CI], 12.1% to 39.5%) as evidenced by improvement in pain intensity, analgesic consumption, and/or Karnofsky performance status. Three (7.3%) of the 41 patients with measurable disease had an objective response (partial). The median time to objective response was 85 days (range, 47 to 91 days) and duration of response was 208, 260, and 566 days for the three responding patients. One patient with nonmeasurable but assessable disease had improved residual disease with a positive clinical benefit response, for a total of four responses among the 42 assessable patients, for an overall response rate of 9.5% (90% CI, 3.3% to 20.5%). Capecitabine was generally well tolerated.

CONCLUSION

Treatment with capecitabine resulted in clinically significant beneficial effects on tumor-related symptoms and yielded objective response activity in patients with metastatic or locally advanced pancreatic cancer. These results together with its generally tolerable safety profile and the added advantage of oral administration provide the basis for further evaluating capecitabine as a single agent or in combination with other treatment modalities in this patient population.

Intrathecal treatment of neoplastic meningitis due to breast cancer with a slow-release formulation of cytarabine

DepoCyte is a slow-release formulation of cytarabine designed for intrathecal administration. The goal of this multi-centre cohort study was to determine the safety and efficacy of DepoCyte for the intrathecal treatment of neoplastic meningitis due to breast cancer. DepoCyte 50 mg was injected once every 2 weeks for one month of induction therapy; responding patients were treated with an additional 3 months of consolidation therapy. All patients had metastatic breast cancer and a positive CSF cytology or neurologic findings characteristic of neoplastic meningitis. The median number of DepoCyte doses was 3, and 85% of patients completed the planned 1 month induction. Median follow up is currently 19 months. The primary endpoint was response, defined as conversion of the CSF cytology from positive to negative at all sites known to be positive, and the absence of neurologic progression at the time the cytologic conversion was documented. The response rate among the 43 evaluable patients was 28% (CI 95%: 14-41%); the intent-to-treat response rate was 21% (CI 95%: 12-34%). Median time to neurologic progression was 49 days (range 1-515(+)); median survival was 88 days (range 1-515(+)), and 1 year survival is projected to be 19%. The major adverse events were headache and arachnoiditis. When drug-related, these were largely of low grade, transient and reversible. Headache occurred on 11% of cycles; 90% were grade 1 or 2. Arachnoiditis occurred on 19% of cycles; 88% were grade 1 or 2. DepoCyte demonstrated activity in neoplastic meningitis due to breast cancer that is comparable to results reported with conventional intrathecal agents. However, this activity was achieved with one fourth as many intrathecal injections as typically required in conventional therapy. The every 2 week dose schedule is a major advantage for both patients and physicians.

[On the Brazilian National Medical Educational Examination]

In Brazil, implementation of the so-called "Provão", or National Medical Course Examination, has raised numerous levels of discussion. This article aims to identify patterns in some of the more controversial issues: whether the Exam is really an instrument for evaluation of medical courses themselves, or that of future physicians; adequacy of assumptions underlying the questions as formulated; and lack of precision in the questions.

Fatal cardiomyopathy in dystrophic epidermolysis bullosa

Two unrelated children with autosomal recessive dystrophic epidermolysis bullosa (RDEB) developed fatal dilated cardiomyopathy. Both were malnourished and had severe growth problems. We believe that the most likely cause for the cardiomyopathy is a micronutrient deficiency, most probably selenium deficiency, since the serum selenium level was found to be reduced in the case in whom we measured this, and in 14 of 25 other children with dystrophic epidermolysis bullosa. Echocardiographic screening of 18 other patients revealed no evidence of cardiomyopathy. We recommend careful attention to nutrition, with prospective monitoring of vitamins and micronutrients including selenium and carnitine, and regular echocardiographic screening of patients with severe RDEB.