Catabasis routed after DMD trial failure

The data come just a few weeks after it posted more positive signals from a phase 1 study

The approval by the FDA last year for Sarepta’s DMD drug Exondys 51 (eteplirsen) buoyed many in this research space, but last night we were all reminded of how tough this disease area can be after Catabasis posted disappointing data for its candidate edasalonexent.

Like much of biotech after Trump’s pharma fireside chat yesterday, its shares ended the day up nearly 3%, boosted by talk of slashing FDA regulations and what some interpreted as a slightly lighter tone on pricing.

But they came crashing down just a few hours later when, after hours, the biotech’s shares tanked 65% after top-line phase 2 data showed edasalonexent (a.k.a. CAT-1004) after failing to beat out placebo in 31 Duchenne patients with the measure of change in lower leg muscles.

Edasalonexent is an oral NF-kB inhibitor and—unlike other DMD therapies such as Sarepta's injectable Exondys 51 (eteplirsen) which was approved last year for a specific genetically-defined group of patients—could potentially be used in patients regardless of their underlying mutation, says the company.

Just two weeks back the biotech also posted a phase 1 trial that showed its drug was found to be safe when given to adults and reduced levels of NF-kb, an inflammatory mediator that the company believes is activated in the very early stages of DMD and is critical to the progressive muscle degeneration seen in the disease. 

The data were published in the Journal of Clinical Pharmacology, and saw its shares up 20% on that positive turn.

But its latest phase 2 trial, known as Part B of MoveDMD, was always the bigger test, and its failure has proved disastrous for the company. It said in a statement that it plans to: “Complete a full analysis of the data from Part B of the MoveDMD trial and to submit the data for presentation at an upcoming scientific conference.” Its shares ended at just $1.38 last night.

Jill Milne, CEO of Catabasis, said: “Although we did not meet the MRI T2 composite end point, the continued safety, tolerability and plasma exposure data in Part B of the MoveDMD trial are reassuring.

There is an open-label extension portion of this test, known as Part C, that is still ongoing; Catabasis says it intends to report the results from Part C in 2017, with an interim update in Q2.

Milne added: “We observed potential treatment-associated effects at 12 weeks in the 100 mg/kg/day treatment group, which we believe warrant further evaluation to see if the signals strengthen in the longer-term data from the ongoing open-label extension. Following additional data analysis from the open-label extension, we will determine the next steps for edasalonexent in DMD.”

This will be doubly damaging to the company given that it comes just a few months after writing off its midstage cholesterol drug CAT-2054. The biotech is also developing the NF-kB inhibitor for Friedreich’s ataxia, amyotrophic lateral sclerosis and cystic fibrosis.