A phase 2 dose-finding study of PEGylated recombinant methionyl human soluble tumor necrosis factor type I in patients with rheumatoid arthritis.

OBJECTIVE: In a phase 2 study, to assess the efficacy and safety of pegsunercept, a soluble tumor necrosis factor receptor type I, for the treatment of rheumatoid arthritis (RA). METHODS: Patients were randomized to receive weekly subcutaneous injections of placebo (n = 61) or active drug [400 microg/kg (n = 67) or 800 microg/kg (n = 66)] for 12 weeks. The primary efficacy endpoint was American College of Rheumatology 20% response (ACR20) at Week 12. Secondary efficacy measures included ACR50 and ACR70 responses, and changes in individual ACR components at Week 12. Safety assessments included summaries of adverse events including infectious episodes. RESULTS: Treatment with pegsunercept resulted in a significantly higher ACR20 response at Week 12 in the 800 microg/kg group (45%) compared with the placebo group (26%; p = 0.020). The treatment effect of pegsunercept (both doses) over the study period showed statistically significant improvement for most ACR components and health related quality of life, with the 800 microg/kg group showing greater clinical improvements in efficacy measures. The overall incidence of adverse events and infectious episodes was similar among the treatment and placebo groups. CONCLUSION: In this 12 week dose-finding study of 194 patients, weekly subcutaneous dosing with pegsunercept showed beneficial effects in improving the signs and symptoms of RA. It appeared to be safe and well tolerated in this small number of patients. Significant clinical improvements were seen in patients in the 800 microg/kg group; however, this dose may be suboptimal, and further evaluation of this product with higher doses or a more frequent dosing regimen is warranted.

The effects of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) on platelet recovery in breast cancer patients undergoing autologous bone marrow transplantation.

OBJECTIVE: To assess the safety and efficacy of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) administered after autologous bone marrow transplantation (ABMT). PATIENTS AND METHODS: Two randomized, double-blind, placebo-controlled studies were done. In the phase 1/2 study, 75 breast cancer patients underwent a bone marrow harvest and myeloablative STAMP V chemotherapy and were randomized to receive placebo or one of three doses of PEG-rHuMGDF. In the phase 3 study, 64 patients were randomized to receive placebo or the minimally effective dose of PEG-rHuMGDF. The study drug was administered daily starting on the day of bone marrow infusion until the platelet count was greater than or equal to 50 x 10(9)/L (without transfusion) or for a maximum of 28 days. All patients received 10 microg/kg/day filgrastim starting on day 2 until neutrophil count recovery. RESULTS: PEG-rHuMGDF appeared to be safe and well tolerated. No significant differences were noted in mortality or disease progression rates. Antibodies to MGDF were not observed. In the phase 1/2 study, the time to platelet recovery to greater than or equal to 20 x 10(9)/L and platelet transfusion requirements were significantly reduced for patients treated with PEG-rHuMGDF compared with placebo (p < 0.05). In the phase 3 study, no significant differences in the kinetics of early thrombopoiesis or platelet transfusions after ABMT were observed. CONCLUSIONS: PEG-rHuMGDF was not consistently efficacious in reducing the duration of severe thrombocytopenia. The maximum platelet counts for PEG-rHuMGDF-treated patients occurred a median of 2 weeks after the last dose of drug, suggesting that the biologic effects of this hematopoietic cytokine are delayed compared with other hematopoietic cytokines.