Chasing Lilly and Pfizer, Concert's JAK inhibitor hits high notes in phase 3 alopecia trial

Concert Pharmaceuticals has hit the high notes in a phase 3 alopecia areata clinical trial, finding 41.5% of people had at least 80% scalp hair coverage after taking the high dose of its JAK inhibitor. The data put Concert in the wings as Eli Lilly and Pfizer prepare to take to the stage and compete for the market.

The clinical trial randomized 706 adults with moderate to severe alopecia areata to receive one of two doses of CTP-543, 8 mg or 12 mg, or placebo twice a day for 24 weeks. At baseline, the average score on the Severity of Alopecia Tool (SALT) was 85.9, indicating that the patient population had less than 15% scalp hair coverage. Participants needed to have at least 50% scalp hair loss to enroll.

After 24 weeks of treatment, 41.5% of patients on the high dose of CTP-543 had at least 80% scalp hair coverage, as measured by a SALT score of 20 or less. Scalp hair coverage in the low-dose arm was 29.6%. With 0.8% of people on placebo having 80% or greater coverage, the treatment difference for both dose groups was statistically significant and the trial hit its primary endpoint, with the p value coming in at less than 0.0001.

Shares in Concert rose 7% to just shy of $5 in premarket trading. 

Concert is yet to share a detailed look at the secondary endpoints but the top-line findings are positive—or, according to Mizuho Securities, "highly positive." Both dose groups met secondary endpoints that looked at the percentage of responders on a patient satisfaction scale and the percentage of patients achieving absolute SALT scores of 20 or less at four time points before week 24.

The data compare favorably to recent results on Lilly and Incyte’s rival JAK inhibitor Olumiant in patients with alopecia. In studies intended to support regulatory approvals this year, Lilly found 39% of patients had at least 80% scalp hair coverage after 52 weeks. Baseline coverage was just less than 15%, as it was in Concert’s study. Pfizer’s JAK3/TEC inhibitor ritlecitinib also hit the endpoint in a phase 2b/3 study. 

Mizuho believes Concert has potentially reported best-in-class efficacy data over Olumiant and Pfizer's offering. 

On the safety front, Concert saw two serious adverse events in one patient that were possibly related to the treatment. The most common side effects, affecting more than 5% of patients, included headache, acne, upper respiratory infection and increased creatine kinase levels. Upper respiratory infections were more common in the placebo than in the treatment arms, and no patients had pulmonary embolisms or deep vein thrombosis. Two patients on CTP-543 developed shingles. 

Notably, Concert did not report any pulmonary embolisms or deep vein thromboses during the trial, both adverse events that have been concerns with other oral JAK inhibitors, Mizuho said. About 14 patients did drop out of the trial due to adverse events, but this was balanced across the treatment and placebo arm, the firm noted. 

Even though Concert appears to have the lead on efficacy, Mizuho said the company faces a few hurdles. First, CTP-543 has to be taken twice a day compared to Lilly and Pfizer's therapies that are once-daily. And the Big Pharmas are likely to beat Concert to market by at least a year, meaning those treatments will be well established before the smaller biotech gets started with marketing. 

With that said, Mizuho noted "there is a significant unmet need in alopecia areata and dermatologists we have spoken to previously have mentioned that the product that delivers the most efficacy will likely be the one they end up prescribing the most for their patients."

Peak sales for CTP-543 could reach $800 million, according to Mizuho. 

Concert is now working to wrap up a second phase 3 clinical trail that is scheduled to deliver top-line data in the third quarter, with a view to filing for FDA approval in the first half of next year. James Cassella, chief development officer at Concert, was upbeat after getting a look at the data from the first study. 

“With these compelling phase 3 data, we believe that CTP-543 has the potential to be a best-in-class treatment for patients with alopecia areata, a disease that has long been ignored. We’re working to change the treatment landscape and hope that CTP-543 will be one of the first FDA-approved treatment options for this serious disease,” Cassella said in a statement.

Editor's Note: This article was amended at 10:21 a.m. ET on May 23, 2022, to add analyst commentary.