Callisto Pharmaceuticals has been granted orphan drug designation for Atiprimod, its drug candidate for carcinoid tumors. Atiprimod is a small molecule orally available drug with antiproliferative and antiangiogenic activity.
“Callisto is planning an ambitious program of clinical development of Atiprimod in the carcinoid indication,” asserts Gary S. Jacob, Ph.D., CEO, “and the designation of orphan drug status gives additional assurance that we are well protected against any potential competition.”
Callisto plans to begin a single-agent Phase II trial of Atiprimod in advanced carcinoid cancer patients in the third quarter of 2006. “We are very excited to be able to go directly into a pilot phase II clinical trial planned to involve approximately 30 patients to determine this drug's efficacy in a tumor where patients have very few treatment options,” comments Arthur Sytkowski, M.D., consulting CMO and medical monitor. “The tumor regression and reduction in symptoms seen in the carcinoid patients from the earlier advanced cancer trial is very encouraging and indicates that a Phase II trial of Atiprimod specifically to treat advanced carcinoid patients is clearly warranted.”
The drug has been shown to inhibit secretion of VEGF and IL-6, elicit an apoptotic response, and inhibit phosphorylation of key kinases involved in tumor progression and survival, including Akt and STAT3.
Originally planned as a Phase I/IIa trial, the decision to proceed directly to Phase II was based on data from the two ongoing trials of Atiprimod in advanced cancer and multiple myeloma patients. The Phase I trial found that the drug candidate showed encouraging activity in a cohort of carcinoid cancer patients, states Callisto. Of the five patients on the drug, three had measurable tumor regressions and loss of debilitating symptoms. One patient remained on the drug through seven cycles (seven months), exhibiting significant tumor regression.