Japan's Otsuka ends pacts with Acucela after trial failure


Tokyo-based Otsuka Pharmaceutical scrapped two licensing deals with ophthalmic biotech Acucela following disappointing Phase III results for the venture's lead candidate, ACU-4429 (emixustat), which is being developed to treat dry age-related macular degeneration, a serious eye condition that can cause blindness.

A pact between Otsuka and Tokyo-listed Acucela dating to 2008 had the two firms working jointly on development and commercialization efforts for the candidate that targeted the RPE65 enzyme to reduce the accumulation of retinoid-related toxic metabolites.

But ACU-4429 missed its primary endpoint in a U.S. Phase IIb/III trial of 508 patients, according to data released last month. It failed to show any significant difference in a once-daily regimen compared to a placebo.

"Following a review of the clinical trial data, Otsuka decided to end its participation in further development activities for ACU-4429 and informed Acucela of its decision to terminate the agreement upon the lapse of a pre-determined notification period," the company said in a statement. 

Acucela raised more than $160 million in 2014 in Japan via an initial public offering, allowing the firm headed by Japanese eye specialist Ryo Kubota to straddle operations between its Seattle headquarters in the U.S. and Japan.

The other candidate in the collaboration, OPA-6566, was developed by the Japanese firm to treat glaucoma under a 2010 pact. But this collab will also now be axed.

"In addition, Otsuka simultaneously informed Acucela of its decision to end their collaboration for OPA-6566 for glaucoma, exercising its contractual right to terminate the agreement upon the lapse of a pre-determined notification period," Otsuka said. "The two companies originally signed a co-development and co-commercialization agreement for the compound in September 2010. Otsuka OPA-6566 is in development in the U.S., where a Phase I/II clinical trial has been completed."

Otsuka was not immediately available to comment on future plans for OPA-6566.

- here's the release