Seagen and Genmab win quick FDA approval

Cervical  Cancer Drug

The US Food and Drug Administration (FDA) has approved Seagen and Genmab's drug Tivdak “for patients with cervical cancer whose tumors have relapsed or spread after chemotherapy,” reported Jonathan Gardner of BioPharma Dive. Tivdak is reportedly the first of its kind to target a protein called tissue factor that is often expressed on cancerous cells. The companies established the drug's list price at approximately $34,000 a month.

The approval of Tivdak is the fourth for both Seagen and Genmab. Genmab has launched other products in partnership with Johnson & Johnson, Novartis and Roche. Tivdak, an "antibody-drug conjugate," is composed of a protein-targeting antibody owned by Genmab and Seagen technology that links a tumor-killing chemical.

Tivdak garnered accelerated clearance based on study results showing that it reduced tumors in a patient group with limited treatment options. “Seagen and Genmab will need to confirm its safety and effectiveness in a trial that will test whether it can help patients live longer than those on chemotherapy,” Gardner said.

Tivdak gives doctors and patients another option for a disease that has had few advances in treatment beyond traditional chemotherapy. Roche's Avastin and Merck & Co.'s Keytruda, recent drugs to serve the need for relapsed cancer, have shown only modest effectiveness. Avastin combined with chemotherapy improved survival by about four months as compared with chemotherapy alone, while Keytruda reduced or eliminated tumors in about 14 percent of patients whose cancer expressed a protein marker associated with treatment responses.

Tivdak has shown signs that it works without chemotherapy, as Avastin does, and in a broader patient population than Keytruda does. In a small trial called InnovaTV 204 that supported accelerated approval, treatment with Tivdak reduced or eliminated tumors in 24 percent of patients whose cancer had progressed following Avastin plus chemo and up to one other prior therapy. Seven percent of study participants had complete responses to treatment.

Earlier in 2021, Seagen and Genmab began enrolling patients into a larger trial called InnovaTV 301 to confirm that Tivdak can help patients live longer than chemotherapy, but that trial may not return results for three years. Meanwhile, the two partners have been testing the treatment in patients with earlier-stage disease.

At the European Society for Medical Oncology Meeting, seagen and Genmab released data from another trial called InnovaTV 205, which tested Tivdak in a number of combinations and settings. In patients who have never received a systemic treatment before, Tivdak plus chemo shrank or eliminated tumors in 55% of patients, helping them live a median of greater than nine months without their disease progressing. With Keytruda in patients following two or three prior treatments, Tivdak shank or eliminated tumors in 38% of patients and led to median progression-free survival of nearly six months.

However, in earlier-stage disease, Keytruda has shown more impressive effectiveness, reducing the risk of death by more than 30 percent in the KEYNOTE-826 trial, which paired it with chemotherapy and Avastin. Stephen Willey, an analyst at Stifel, wrote in a September 19 note to clients that those data suggest Keytruda will need to be a part of an early-line therapy combination.

Seagen launched its first product, an antibody-drug conjugate called Adcetris, in 2011. Since late 2019, the Seattle-based biotech company has now won approvals for three more, and last year turned a profit for the first time because of revenues from license agreements. Tivdak could further added to Seagen's bottom line. Approvals for Seagen’s second and third drugs were quickly followed by a billion-dollar deal with Merck.