Renato V. La Rocca

Multicenter, Randomized Trial for Stage IIIB or IV Non–Small-Cell Lung Cancer Using Weekly Paclitaxel and Carboplatin Followed by Maintenance Weekly Paclitaxel or Observation

PURPOSE To explore the efficacy and safety of three regimens of weekly paclitaxel plus carboplatin as initial therapy and the feasibility of subsequent maintenance therapy versus observation in patients with advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Four hundred one patients were randomly assigned to one of the following arms: arm 1, paclitaxel 100 mg/m2 weekly for 3 of 4 weeks with carboplatin (area under the curve [AUC] = 6) on day 1; arm 2, paclitaxel 100 mg/m2 and carboplatin (AUC = 2) weekly for 3 of 4 weeks; or arm 3, paclitaxel 150 mg/m2 cycle 1 and 100 mg/m2 cycle 2 and carboplatin (AUC = 2) weekly for 6 of 8 weeks. Patients who responded (n = 130) at week 16 were randomly assigned to either weekly paclitaxel therapy (70 mg/m2, 3 of 4 weeks; n = 65) or observation (n = 65). RESULTS For the 390 assessable patients, the objective response rates observed with initial therapy were 32% for arm 1, 24% for arm 2, and 18% for arm 3. The median time to progression and median survival times were 30 and 49 weeks for arm 1, 21 and 31 weeks for arm 2, and 27 and 40 weeks for arm 3, respectively. The 1-year survival rates were 47% for arm 1, 31% for arm 2, and 41% for arm 3. CONCLUSION Arm 1, paclitaxel 100 mg/m2 weekly for 3 of 4 weeks with carboplatin (AUC = 6) administered on day 1, demonstrates the most favorable therapeutic index in patients with advanced NSCLC.

EFFECT OF SURAMIN ON HUMAN PROSTATE CANCER CELLS IN VITRO

Suramin, a polyanionic compound with known antiparasitic activity, has been shown to be adrenocorticolytic in primates and to have clinical efficacy in the treatment of patients with metastatic prostate cancer refractory to conventional hormonal manipulation. To better characterize the activity of suramin on prostate cancer biology, we studied the effect of the drug on plasma adrenal androgens of patients and on the human prostate adenocarcinoma cell lines PC-3, DU 145 and LNCaP-FGC. Five cancer patients treated with suramin had an approximate 40% decline in circulating androstenedione, dehydroepiandrosterone and dehydroepiandrosterone sulfate levels. The drug inhibited the colony formation in two of the three cell lines at concentrations clinically achievable in humans without excessive drug-related toxicity. The presence of suramin 300 micrograms./ml. partially inhibited the growth stimulatory effect of testosterone and basic fibroblast growth factor, but not that of epidermal growth factor. The cellular concentration of suramin following exposure to a single dose increases linearly over time in each of the cell lines with LNCaP-FGC accumulating the highest levels of the drug; cellular levels of suramin, not androgen or growth factor sensitivity, correlated with the sensitivity to the drug. The concentrations of prostatic acid phosphatase and prostatic specific antigen released by LNCaP-FGC cells in cell culture medium declined in the presence of increasing levels of suramin in a manner which exceeded the decrease in cell number. We conclude that suramin, aside from decreasing circulating androgens through its adrenocorticolytic effect, is also capable exerting a direct inhibitory effect on cell proliferation of prostate cancer cells, and interfere at a cellular level with the growth stimulatory effects of exogenous testosterone and basic fibroblast growth factor.

Suramin, a novel antitumor compound

Suramin, a polyanionic compound originally synthesized for use as an antiparasitic agent, has recently entered clinical trials for the treatment of a variety of human cancers refractory to conventional modalities of therapy. This is based on suramins ability to bind and to inactivate growth factor and enzyme systems critical to cellular homeostasis and proliferation. In addition, this compound possesses adrenocorticolytic properties in vivo and exerts significant cytostatic and cytocidal effects against a variety of human tumor cell lines in vitro. Pilot studies using suramin have thus far been conducted in adrenocortical carcinoma, prostate cancer refractory to conventional hormonal manipulation and nodular lymphomas.

Adaptive control with feedback strategies for suramin dosing

Suramin, a drug used in the treatment of parasitic diseases, is currently being evaluated in clinical trials as an antineoplastic agent. The use of therapeutic drug monitoring and adaptive control with feedback in clinical trials of suramin was initially motivated by an association between acute neurologic toxicity and plasma suramin concentrations in excess of 350 μg/ml. We have prospectively examined the performance of both two‐ and three‐compartment population pharmacokinetic models in controlling plasma suramin concentrations and have found that a three‐compartment model best describes this drug. No correlation was found between the clearance of suramin and creatinine clearance, as had been previously hypothesized. The low systemic clearance of suramin and the number of parameters required to describe the three‐compartment model suggest the need for a bayesian approach to the estimation of individual pharmacokinetics.

Comparison of outcomes for elderly patients treated with weekly paclitaxel in combination with carboplatin versus the standard 3‐weekly paclitaxel and carboplatin for advanced nonsmall cell lung cancer

The purpose of this study was to compare the outcomes between elderly (aged ≥70 years) patients treated with paclitaxel on a weekly basis and with carboplatin (every 4 weeks) versus the standard 3‐weekly regimen of carboplatin and paclitaxel for first‐line therapy of advanced nonsmall cell lung cancer.

Treatment of Elderly Non–small Cell Lung Cancer Patients with Three Different Schedules of Weekly Paclitaxel in Combination with Carboplatin: Subanalysis of a Randomized Trial

Background: Administration of paclitaxel on a weekly schedule in combination with carboplatin is associated with a lower incidence of neuropathy and myelosuppression. The authors conducted subgroup analysis of their randomized phase II study of three different schedules of weekly paclitaxel with carboplatin to determine the efficacy of each regimen in elderly patients (aged ≥ 70 years) with advanced non–small-cell lung cancer (NSCLC). Methods: Patients with advanced NSCLC were randomized to one of three different weekly paclitaxel/carboplatin regimens. After four cycles of chemotherapy, those with objective response or stable disease were randomized to weekly paclitaxel or observation as maintenance therapy. Four hundred three patients were enrolled in the study, of whom 111 (28%) were aged 70 years or older. Results: The treatment regimen of weekly paclitaxel (100 mg/m2 for 3 of 4 weeks) and carboplatin (area under the curve = 6 mg/ml/min once every 4 weeks) (arm 1) was associated with the best therapeutic index overall. The median survival and 1-year survival rates were 11.3 months and 50% for patients in the ≥70 years cohort versus 11.2 months and 46% for the <70 years cohort in arm 1. Efficacy results were comparable between the two groups in the other arms as well. Grade 4 neutropenia and febrile neutropenia occurred in 13.6% and 2.3% in the ≥70 years cohort compared with 4.5% and 1.1% in the <70 years cohort in arm 1. Conclusion: The weekly regimen of paclitaxel administered in combination with carboplatin is tolerated well by elderly NSCLC patients and has comparable efficacy with younger patients.

CARDIAC TOXICITY AND ANTITUMOR-ACTIVITY OF 4'-DEOXY-4'-IODO-DOXORUBICINOL

SummaryThe acute and chronic cardiotoxicity as well as the cytotoxicity of 4′-deoxy-4′-iodo-doxorubicinol (I-DXRol), the major metabolite of the doxorubicin (DXR) derivative 4′-deoxy-4′-iodo-DXR (I-DXR), were compared with those of I-DXR and DXR. In the acute study, anesthetized rats received i. v. DXR (10 mg/kg), I-DXR (4 mg/kg), or I-DXRol (4 mg/kg) and were monitored for ECG (SαT segment and T wave), systolic (SBP) and diastolic (DBP) blood pressure, the first derivative of the systemic arterial pressure (SA dP/dtmax), and heart rate. Treatments induced a significant widening of the SαT segment, but I-DXRol was significantly less toxic than I-DXR or DXR. As compared with control values, DXR induced a marked increase in SBP and DBP and a decrease in SA dP/dtmax, whereas I-DXR and I-DXRol induced modest changes in hemodynamic parameters. In the chronic study, 3 mg/kg DXR given to rats by i.v. bolus once a week for 3 weeks resulted in severe chronic cardiotoxicity that lasted 6 weeks and was characterized by SαT-segment widening, T-wave flattening, and severe cardiac histological damage. Doses of 1.2 mg/kg I-DXR and 1.2 and 2.4 mg/kg I-DXRol, given i.v. once a week for 3 weeks, and 3.6 mg/kg I-DXRol given as a single dose were associated with a significant T-wave voltage reduction; I-DXR and 2.4 mg/kg I-DXRol induced significant histological alterations of cardiac tissue as compared with control values, whereas modest alterations of heart tissue were observed after injections of 1.2 and 3.6 mg/kg I-DXRol in three doses and in a single dose, respectively. The cytotoxicity of the three anthracyclines against one glioblastoma cell line and two human small-cell lung cancer lines was similar. Results indicate that the acute cardiotoxicity of I-DXRol is lower than that of I-DXR and DXR, whereas the chronic heart damage is similar to that induced by I-DXR and significantly lower compared than that caused by DXR. Moreover, the cytotoxicity of the metabolite appears to be similar to that of I-DXR and DXR. The lack of additional cardiac toxicity due to I-DXRol further supports the lower overall cardiac toxicity of I-DXR, which retains a cytotoxic activity similar to that of the parent drug.