BioCryst reports results from forodesine studies for CTCL and CLL

Sep 15 2010

BioCryst Pharmaceuticals, Inc. (NASDAQ: BCRX) announced preliminary top-line results from its multinational, open-label, single-arm trial evaluating 200 mg once-daily oral forodesine in the treatment of relapsed or refractory cutaneous T-cell lymphoma (CTCL), as well as interim results from the Company's exploratory Phase 2 study to investigate the efficacy and safety of 200 mg twice-daily oral forodesine as monotherapy for chronic lymphocytic leukemia (CLL).

“Two-thirds of the late-stage CTCL patients experienced stable disease or better, and forodesine was generally safe and well-tolerated at the dose evaluated in this study. The eleven percent response rate observed in this study population may reflect the impact of heavy pretreatment with multiple prior lines of therapy.”

"These data expand our understanding of the potential role for forodesine and other purine nucleoside phosphorylase inhibitors in the treatment of patients with hematological malignancies," said Jon P. Stonehouse, President and Chief Executive Officer of BioCryst. "We believe PNP inhibition is a potentially interesting mechanism for combination with other therapies and for earlier lines of therapy, based on the clinical activity and tolerability of forodesine."

CTCL study top-line results

The study's primary endpoint was objective response rate, defined as complete or partial cutaneous response that is sustained for at least 28 days, in patients with later stage (stage IIB, III and IVA) disease who had previously received at least three systemic therapies for their disease. Eleven of 101 (11% [95% confidence interval: 6-19%]) later stage patients enrolled achieved a partial cutaneous response, while no patients achieved a complete response. Of the remaining later stage patients, 56 (55%) had stable disease as their best response, 30 (30%) had progressive disease, with a median time to progression of 353 days, and four (4%) were not evaluable. The median number of prior systemic therapies was four (range 3-15) among patients with later stage disease. Oral forodesine was generally safe and well-tolerated in this study, and was administered daily for up to 839 days.

"Heavily pretreated CTCL patients are in need of additional treatment options," said Dr. William P. Sheridan, Chief Medical Officer at BioCryst. "Two-thirds of the late-stage CTCL patients experienced stable disease or better, and forodesine was generally safe and well-tolerated at the dose evaluated in this study. The eleven percent response rate observed in this study population may reflect the impact of heavy pretreatment with multiple prior lines of therapy."

Eligible patients were those with CTCL of stages IB through IVA who have disease that was persistent, progressive or recurrent during or after treatment with at least three systemic therapies, one of which must have been oral bexarotene. A total of 144 patients with CTCL, with a median duration of illness of 52.5 months, were enrolled. The most common adverse events reported were peripheral edema, fatigue, insomnia, diarrhea, headache and nausea.

This trial was conducted under a Special Protocol Assessment (SPA) agreement negotiated with the U.S. Food and Drug Administration (FDA). Further details regarding the study design are available at the following clinicaltrials.gov link: http://clinicaltrials.gov/ct2/show/NCT00501735.

Exploratory Phase 2 CLL study interim results

This ongoing study enrolled 25 CLL patients who had failed at least one prior treatment regimen. The primary endpoint of this single-arm, open-label study was overall response rate. The interim analysis showed that three patients demonstrated a confirmed partial response to forodesine. Six patients remain enrolled in the study and on treatment. Five of the patients have been treated with forodesine twice-daily for longer than one year. Consistent with results of previous clinical trials, forodesine was generally safe and well-tolerated in this study. Final results from this study are expected later in 2010, and the Company plans to present the final results for presentation at an upcoming medical meeting.

"We are very encouraged with the response rate observed for forodesine administered as a single agent twice-daily in this refractory or relapsed CLL patient population," added Dr. Sheridan. "The efficacy, safety, tolerability and oral administration of the PNP inhibitor forodesine support its continued evaluation for this disease. In addition, these characteristics make forodesine attractive to combine with other active drugs for treatment of CLL."

Further details regarding the study design of the CLL study are available at the following clinicaltrials.gov link: http://clinicaltrials.gov/ct2/show/NCT00640523

Source: http://www.biocryst.com/