Sinking Marinus gets a lifeline with new ganaxolone data

Micro cap Marinus Pharmaceuticals was up 28% premarket this morning on positive, early data from its midstage test of ganaxolone in a rare condition that causes severe seizures.

This has buoyed the company that was trading just over $1 at end of play last week (with a market cap of just $22 million), coming off the back of a tough second half of 2016 when in the summer, it pulled the plug on the ganaxolone testing program in adult focal onset seizures.

This came after the med, a CNS-selective GABAA modulator, failed to best placebo in a phase 3 study. Its shares were hit hard, down 70% on the news back in June, where it had been trading at around $6 a share.

Today, however, there is a crack of light for the drug in patients with CDKL5, a rare genetic disorder that results in early-onset, difficult-to-control seizures, and neuro-developmental impairment.

The data are only preliminary and comes out of the initial CDKL5 patients enrolled in the biotech’s ongoing phase 2, open-label study, but this has been enough to see the small boost to its share price.

Enrollment is continuing in the study with top-line data expected in mid-2017, but so far, four patients have been enrolled in this cohort and received up to 1,800 mg/kg of ganaxolone per day for five months.

The biotech said three of the four patients “experienced a notable reduction in seizure frequency compared to baseline ranging from 52% to 88%.”

One patient, however, was said to have stopped taking the drug and left the test after four months of treatment “due to lack of efficacy.” Marinus added that the drug appeared to be safe and well tolerated.

The study, which will be split across several cohorts, is slated to enroll up to 10 patients with each of CDKL5 disorder, Lennox Gastaut Syndrome and PCDH19 pediatric epilepsy.

Jaakko Lappalainen, VP of clinical development at Marinus, said: “Concurrent with completing this study, we will be evaluating the potential for breakthrough therapy and applying for orphan drug designation with the United States Food and Drug Administration. CDKL5 pediatric epilepsy may prove to be an attractive and efficient path for ganaxolone and we look forward to evaluating results from the final patients enrolled in this cohort of the study.”

Michael G. Chez, director of pediatric neurology research and pediatric epilepsy, Sutter Neuroscience Institute in Sacramento, CA, added: “I am impressed with the responder rate and magnitude of seizure control seen with ganaxolone in the initial CDKL5 patients. The CGIs (clinical global impression scales) are consistent with seizure control, with responders showing ‘much improved’ under this scale. I look forward to further evaluating these children and seeing the final results.”