to combine the precise targeting capability of an antibody drug, with super-potent toxins that have extra tumor-killing capability. Roche’s U.S.-based Genentech unit has released promising data for one such empowered antibody in the past year, but after it suffered a setback with the FDA, Seattle Genetics may now be in position to get its drug on the U.S. market first.
Millennium, through a partnership it struck a year ago, holds commercial rights to the product outside North America, where it says it plans to talk with regulators in Europe and other countries “as soon as possible” about how to bring the drug to market.
“We are thrilled to report these impressive data in this highly refractory patient population with a high unmet medical need,” said Nancy Simonian, Millennium’s chief medical officer, in a statement.
The markets for brentuximab vedotin so far are small. But because of the way the drug works against the CD30 target, Seattle Genetics is looking for other tumor types that also have a high number of those targets on their cell surface, which might make them vulnerable to brentuximab vedotin. The list of cancers Seattle Genetics is considering includes cutaneous lymphoma, peripheral T cell lymphoma, bone cancers, and diffuse large B-cell lymphoma, Siegall says. The drug, he says, has “much more” potential than just as a treatment for Hodgkin’s or anaplastic large cell lymphoma.
—Separately, Seattle Genetics also reported some other results from a study of another “empowered antibody” drug candidate in the works. This drug, SGN-75, is designed to hit a different protein target on cancer cells, called CD70.
Results from the first 16 patients who enrolled in this safety study are being presented today at the European Society of Medical Oncology meeting in Milan, Italy. Researchers there are reporting that one patient with non-Hodgkin’s lymphoma had tumors completely eradicated, while one more with kidney cancer (renal cell carcinoma) had a partial response. Those results were seen during the very initial phase of trials, when doctors are testing tiny doses to make sure they are safe, and gradually escalating doses to find the right balance of safety and effectiveness. That study hasn’t yet reached the maximum tolerated dose, which will inform the company about what its next step could be in clinical trials.
SGN-75 is still in its early development, so it’s premature to say it might offer patients hope. But it is following the same pattern, showing anti-tumor activity at less than optimal doses, which distinguished brentuximab vedotin in its early development. “We’re very excited about this one too, but it’s still early,” Siegall says.
