BioPharma, Pharma

Kodiak Sciences’ trial failure clouds eye drug’s prospects for challenging Eylea

A Kodiak Sciences drug failed to beat a Regeneron Pharmaceuticals product in a key test in the wet form of age-related macular degeneration. The biotech says the failure is due to a subset of undertreated patients, but the results raise the stakes for the drug, its lead product candidate, in other eye diseases.


Kodiak Sciences aims to offer patients an eye drug with a dosing edge over a blockbuster medicine from Regeneron Pharmaceuticals. Preliminary data from a key clinical trial in wet age-related macular degeneration raise questions about whether the Kodiak drug can achieve the goal.

The value proposition of Kodiak’s drug, KSI-301, is that patients taking it should need less frequent injections into the eye compared to Regeneron’s Eylea, administered every two months. But according to a vision test (letters read on an eye chart), KSI-301 did not meet the study’s main goal of showing what’s called non-inferiority—an effect that is roughly the same as the comparator treatment. The Palo Alto, California-based company on Wednesday attributed this failure to the results in “a minority of patients.”

In the wet form of AMD, blood vessels leak blood or fluid into the part of the retina called the macula. It’s currently treated with drugs that block vascular endothelial growth factor (VEGF), a protein that sparks the blood vessel growth that leads to this disease. Regeneron’s Eylea is an anti-VEGF drug. Kodiak’s drug is an antibody designed to block VEGF. It comes from a technology, the Antibody Biopolymer Conjugate (ABC) Platform, that extends how long drug levels last in eye tissues, which in turn extends dosing intervals.

In the Phase 2b/3 test of KSI-301, patients in the Kodiak drug arm were started with monthly doses for three months. After that, they were split into subgroups, treated according to dosing schedules of three, four, or five months. The design of the study did not permit more frequent dosing. For the data analysis, the subgroups were pooled together and compared against the Eylea group. Kodiak attributes the trial failure to the results of some patients in the three-month interval subgroup. For some of the participants in this subgroup, this dosing interval was insufficient to sustain vision improvement, and vision actually deteriorated, the company said in an investor presentation.

The Kodiak drug was safe and well tolerated by patients. No cases of eye inflammation or blockages of blood circulation were reported. Despite the Phase 2b/3 failure in wet AMD, Kodiak is continuing with tests of its drug. In a separate Phase 3 study in wet AMD, patients are receiving monthly doses of KSI-301—a more frequent dosing schedule than Eylea. The drug is also being evaluated in clinical trials underway in retinal vein occlusion (dosing every two months) and diabetic macular edema (dosing as frequently as every two months).

“Allowing treatment with KSI-301 no more often than every 12 weeks after the loading phase for every patient turned out to be insufficient,” Kodiak CEO Victor Perlroth said in a prepared statement. “Nonetheless, we believe the results demonstrate a clear anti-VEGF effect, strong durability and a reassuring safety profile. We think that these data continue to support the potential of our ABC Platform to significantly extend treatment intervals in retinal disorders in a safe and convenient manner.”

Investors took a dimmer view of the results. Shares of the company sank more than 80% on Wednesday.

Photo by Flickr user Ken Teegardin via a Creative Commons license