Cell Therapeutics, Inc. has announced that OPAXIO (paclitaxel poliglumex) has been granted orphan-drug designation by the U.S Food and Drug Administration ("FDA") for the treatment of glioblastoma multiforme ("GBM"), a malignant brain cancer.
Orphan designation was granted based on preliminary activity seen from phase 2 results of OPAXIO when added to standard therapy (temozolamide ("TMZ") plus radiation).
In this study, progression-free and overall survival was encouraging among patients with GBM, including patients whose tumors expressed unmethylated MGMT.
Current standard therapy is less effective in patients with tumors that have unmethylated MGMT, an important DNA repair enzyme.
A randomized trial is now underway for patients with GBM with unmethylated MGMT comparing standard TMZ and radiation to OPAXIO and radiation.
According to the National Cancer Institute, GBM is the most common and deadliest type of primary brain tumor in adults. It is estimated that there will be 10,000-12,000 new cases of GBM diagnosed in the US this year alone.
The standard of care for patients with GBM is a surgical resection, if possible, followed by radiation given with concurrent TMZ. The prognosis for the majority of patients with GBM is poor with less than 25% of patients surviving two years with current therapies.
Survival is shorter for patients whose tumors have active (unmethylated) MGMT.
Orphan-drug designation is granted by the FDA to novel drugs that seek to treat a rare disease or condition. Orphan-drug designation provides substantial potential benefits to the drug developer, including seven years of market exclusivity for the product upon regulatory approval, fee waivers and tax incentives.
Under the leadership of Dr. Howard Safran at Brown University Medical Center, a multicenter Phase 2 study (BrUOG 244) has been initiated comparing the efficacy of OPAXIO plus radiation with that of TMZ plus radiation in newly-diagnosed patients with GBM and unmethylated MGMT.
In approximately 55% of patients with GBM, MGMT is unmethylated, thereby decreasing the efficacy of standard therapy with TMZ plus radiation therapy ("RT").
The randomized study seeks to determine whether OPAXIO plus radiation will improve progression free survival and overall survival when compared to TMZ plus radiation, the current treatment standard in this disease.
"The current randomized trial is based on the encouraging results previously demonstrated with OPAXIO and radiation in patients with newly diagnosed malignant brain cancer and specifically targets GBM patients with a genomic marker, unmethylated MGMT, who are less likely to benefit from the current standard of care TMZ and radiation," stated Howard Safran, M.D., Medical Director of the Brown University Oncology Group.
"We are pleased OPAXIO has been granted orphan-drug designation as patients with this disease have a serious unmet medical need for improved long-term survival particularly when MGMT is unmethylated."