Biogen walks away from Ionis-partnered ALS, Angelman prospects after peek at clinical data

Biogen’s CEO may have been celebrating “turning a corner” last month, but it looks like the drugmaker’s early-stage pipeline hasn’t gotten the message yet.

The Cambridge, Massachusetts-based company announced this morning that it is halting its work on Ionis Pharmaceuticals-partnered oligonucleotides for two different diseases. That includes the amyotrophic lateral sclerosis (ALS) drug BIIB105, which was designed to reduce expression of the ATXN2 gene.

However, a look at the six-month data from the 99-person trial showed that while the antisense oligonucleotide did lower ATXN2, it had no impact on levels of plasma neurofilament light chain, a biomarker of neurodegeneration, Biogen explained in the May 16 release.

This gives the company “confidence that BIIB105 did not slow the disease process,” Stephanie Fradette, head of Biogen’s Neuromuscular Development Unit, said in the release.

“Additionally, BIIB105 did not demonstrate an impact on clinical outcome measures of function, breathing and strength,” Biogen added.

Biogen bailed on another ALS partnership—this time with Karyopharm Therapeutics—back in 2022 after taking a look at phase 1 data. The same year, a different Ionis-Biogen antisense program, BIIB078, was dropped after it didn’t improve ALS symptoms at all in a phase 1 trial.

Today’s news means Biogen no longer has any ALS hopefuls to follow in the footsteps of the FDA-approved Qalsody, which was itself first developed at Ionis. Ionis still has its own phase 3-stage ALS asset in the form of ulefnersen, which is aimed at the genetic form of the neuromuscular disease.

The fallout from Biogen’s Ionis partnership didn’t end with BIIB105, however. The Big Biotech also revealed this morning that it’s washing its hands of Angelman syndrome drug ION582, presumably in response to a separate phase 1/2a trial readout.

Biogen didn’t go into the rationale of its decision to hand ION582 back to Ionis. For its part, Ionis seemed pleased with this morning’s readout, pointing to “consistent effects across multiple objective and subjective measures used to assess functioning in individuals living with Angelman syndrome.”

There are no approved treatments for the syndrome, which is caused by a loss of function in the maternal UBE3A gene and prevents most individuals from speaking or living independently.

ION582 is designed to restore expression of ubiquitin protein in patients. Around 65% of the 51 participants in the trial demonstrated an improvement in cognition when measured on the Bayley-4 assessment of clinical functioning, while 70% showed improvements in communication, Ionis noted.

While “no direct comparisons should be made,” Ionis stressed, both of these changes “exceeded improvements seen in natural history studies over the same time period.” The drug was also safe and well tolerated at all dose levels, meeting the study’s primary objective.

"We are encouraged by the data from the HALOS study and pleased to add this promising medicine to our growing independent pipeline of neurology medicines,” Ionis CEO Brett Monia, Ph.D., said in the release.

“We look forward to sharing detailed data at the upcoming Angelman Syndrome Foundation meeting and to advancing ION582 into a pivotal study,” Monia added.

Biogen may be walking away from both programs, but it isn’t the end of its work with Ionis. The two companies will “continue their long-standing commitment to developing therapies for ALS given the devastating impact of this progressive, fatal neurodegenerative condition,” Biogen said.

The two latest removals from Biogen’s pipeline come a month after CEO Chris Viehbacher told analysts that the company is “turning the corner” after several recent setbacks over a year that saw 1,000 staff laid off and an “extraordinarily difficult launch” for Alzheimer’s disease drug Leqembi.