Are commercial prospects limited for Valeant's Siliq?
- Valeant got a ray of good news late Wednesday, securing approval from the Food and Drug Administration for its anti-inflammatory drug Siliq (brodalumab) in plaque psoriasis.
- But the drug will carry a black box warning for an increased risk of suicidal ideation or behavior and will only be available through a strict Risk Evaluation and Mitigation Strategy (REMS) program that will likely slow uptake.
- Siliq will also have an uphill battle to wrestle market share away from established psoriasis drugs, as well as from more recently launched treatments from Novartis and Eli Lilly & Co which target the same pathway (although binding to a different site).
Approval of Siliq wasn't a sure thing. Amgen, which had originally partnered with AstraZeneca to develop brodalumab, handed back rights to the drug in 2015 after observing events of suicidal ideation — a concern that Amgen thought would necessitate restrictive labeling and limit commercial prospects.
AstraZeneca then out-licensed brodalumab (now Siliq) to Valeant for $100 million upfront later that year. It was part of Valeant's efforts to start doing R&D amidst outcry that it was buying its pipeline and not making anything innovative.
Valeant pushed the drug across the finish line and into regulatory review, securing the backing of an FDA advisory panel last summer despite six observed suicides in clinical trials.
Now, it looks like Amgen's original concerns have come to pass. Not only will Siliq carry a black box warning—the most serious warning the agency hands out, but the FDA also threw up several hurdles restricting the prescribing and dispensing of the drug.
Under a REMS program, physicians will have to be certified to prescribe Siliq and are advised to counsel patients on the risk of suicidal ideation. Patients must sign a consent form and pharmacies are only allowed to dispense the drug if certified under the program.
Siliq is also contraindicated for patients with Crohn's disease, and the FDA advised doctors to screen patients for tuberculosis before prescribing the drug.
Valeant plans to begin marketing the drug in the U.S. in the second half of 2017. In addition to the challenging labeling and risk-management requirements, Siliq will be going up against two fast-growing rival drugs.
Novartis' Cosentyx (secukinumab) and Lilly's Taltz (ixekizumab) are both already approved to treat plaque psoriasis and have quickly racked up sales.
The two drugs target a protein known as IL-17A, preventing that protein from binding to its receptor and thereby limiting inflammatory responses. Siliq also targets the IL-17 pathway, but binds to the receptor itself to inhibit inflammatory signaling.
Cosentyx, which won approval in 2015 and also is indicated for use in ankylosing spondylitis, has already hit blockbuster status, pulling in $1.13 billion in 2016 sales. Taltz, approved in March of last year, earned $113 million in annual sales.
Valeant will need to see solid growth from Siliq as approval of the drug triggered a $130 million milestone payment to AstraZeneca. Per the original licensing deal, the two drugmakers will also split profits in the U.S., limiting Valeant's upside somewhat. (Astrazeneca and Valeant last summer agreed to terminate Valeant's license to brodalumab in Europe, which is now held by LEO Pharma.)
Still, winning approval for a new drug is a welcome change for Valeant, which hasn't yet recovered from a damaging 2016 filled with accounting scandals, pricing controversies, federal investigations, leadership changes and a near-default.
Company CEO Joseph Papa has begun to sell off assets to help pay down Valeant's sizable debt load but the company will need new growth to turn its downward trajectory around. Siliq may help, but the labeling restrictions and competitive market suggest it won't be a cure-all.
- Valeant Press release
- AstraZeneca Form 6K
- BioPharma Dive (A recap:) Valeant wins backing of FDA panel for psoriasis drug
Follow Ned Pagliarulo on Twitter