Lilly Scraps Lupus Drug Candidate
Eli Lilly has given up on its lupus drug candidate tabalumab after researchers determined the efficacy data from two Phase III studies were not strong enough to support a regulatory submission.
The decision last week follows the drugmaker’s move early last year to abandon the drug as a treatment for rheumatoid arthritis, after it, too, performed poorly in clinical trials.
The compound had shown promise as a lupus treatment, the company said. Of four doses studied across the two trials, one met the primary endpoint of statistically significant improvement on the SRI-5 scale of disease and response. But overall, the results weren’t enough to seek FDA approval, the company added.
That decision has left investors disappointed, says ISI Group analyst Mark Schoenebaum. Commercial modeling had estimated the drug would generate between $250 and $300 million in sales, he said. GlaxoSmithKline’s Benlysta (belimumab), the only biologic approved specifically for lupus, currently is generating $200 million worldwide, with sales projected to rise to $600 million, Schoenebaum added.
Clinical development for a highly variable disease like lupus is difficult, says Lilly spokesman J. Scott MacGregor, noting that Benlysta is the only targeted biologic for lupus approved in the last 50 years.
How the disease manifests itself in different groups of lupus patients adds to the development challenge, says Lupus Foundation of America Medical Director Joan Merrill. About half of lupus patients, for example, have very high levels of interferon, while the other half does not, she said.
That complicates clinical trials because many trials allow patients to continue taking other medications, Merrill said. This makes it difficult to determine the study drug’s true efficacy. At the same time, she noted, it would be unethical to either put severely ill patients on a placebo or to categorically exclude healthier patients in order to allow continued use of another lupus medication. — Lena Freund
Originally appeared in Drug Industry Daily, the pharmaceutical industry’s number one source for regulatory news and information. Click here for more information.