Merrimack Pharma Begins Phase 1 Trial Of Brain Cancer Drug

Biopharmaceutical company Merrimack Pharma announced that its Phase 1 clinical study of MM-398 (nanoliposomal irinotecan injection) has begun with the enrollment of the first patient for the trial.

MM-398 is a nanoliposomal encapsulation of the chemotherapy drug irinotecan. In its activated form, the drug is known as SN-38, an inhibitor of a key enzyme in DNA transcription and replication, which, in turn, promotes cell death. Earlier this year, Merrimack collaborated with Baxter International to develop and market MM-398 outside the U.S. and Taiwan in an exclusive licensing agreement.

The dose-escalating, open label, Phase 1 study will evaluate the safety of MM-398 in a highly concentrated formulation when administered by convection-enhanced drug delivery in patients with recurrent high grade glioma. The convection-enhanced drug delivery technique will also give researchers a glimpse as to how the drug reaches the brain. Merrimack stated that the trial will enroll up to 36 patients with recurrent high grade glioma and will take place at the University of California, San Francisco.

Dr. Nicholas Butowski, Associate Professor of Neurological Surgery, who will be leading the study, said, “The blood-brain barrier is known to limit the effective delivery of anti-cancer therapies. By utilizing an imaging-guided, direct-injection technique to deliver MM-398, we hope to increase the cytotoxic effects of the drug on the tumor with less peripheral toxicity and fewer side effects. MM-398 is an excellent candidate for convection-enhanced delivery due to its nanoliposomal design, which may allow the drug to be stably deposited in the tumor, thereby prolonging exposure of the tumor to the drug.”

Daryl Drummond, VP of Discovery at Merrimack, said, “There are few options for patients with recurrent high grade gliomas, as these types of aggressive brain tumors often grow back after surgery and radiotherapy… MM-398 was shown to extend quality of life and survival, and we are pleased to support Dr. Butowski's research.”

A day earlier, Merrimack announced the U.S. Food and Drug Administration (FDA) granted orphan designation to the company’s MM-141 for the treatment of pancreatic cancer.