Amgen says Imdelltra-Imfinzi combo cuts death risk 58% in aggressive lung cancer

The results, presented at the European Society for Medical Oncology Congress, tested the combination as a maintenance therapy in patients who had received initial treatment with Imfinzi and chemotherapy and whose cancer had not progressed. Half of patients in the combination group were alive for at least about 21 months, compared with half in the Imfinzi-alone group at 12.7 months. Amgen said nearly 80% of patients who started both drugs were alive at one year, compared with 53% of those receiving Imfinzi alone.

“I think there are moments in medicine when you see a piece of data that is so profound that it's going to transform the standard of care for patients, and I think, honestly, we're at that moment,” Dr. Paul Burton, Amgen’s chief medical officer, said in an interview with CNBC. Burton said the combination “has the potential to take on one of the most aggressive cancers that we deal with today, and almost convert it into a chronic disease,” adding that the data suggest that is a possibility.

Small cell lung cancer remains difficult to treat because, even if chemotherapy initially works well for most patients, the disease often returns or progresses within months, said lead trial investigator Dr. Jacob Sands, associate chief of the Lowe Center for Thoracic Oncology at Dana-Farber Cancer Institute. He said immunotherapy has helped a small subset of patients achieve years of disease control, but most have not had similarly durable benefits. There are roughly 31,000 new small cell lung cancer cases in the United States each year, and an estimated 60% to 70% of those people are diagnosed with extensive-stage disease, according to CNBC.

Sands said the trial benefits were seen across patient subgroups, including those whose cancer had spread to the brain or liver, locations associated with poorer treatment outcomes. He added that longer-term follow-up data may change the 21-month figure and “hopefully will substantially improve,” similar to what Amgen saw in a Phase 1 trial of the immunotherapy combination. In that earlier, smaller trial, long-term follow-up showed the benefit was sustained for years.

Amgen said the findings suggest using Imdelltra earlier in treatment could meaningfully alter the disease’s trajectory. Imdelltra is currently approved for patients whose small cell lung cancer has progressed during or after platinum-based chemotherapy. Researchers specifically tested whether adding Imdelltra could help patients live longer than continuing Imfinzi alone, which is already approved as a first treatment for this type of lung cancer. The study did not test whether the combination was better than other first-line treatment approaches.

Imdelltra binds to DLL3, a protein on cancer cells, and CD3, a protein on T cells, bringing T cells into close contact with tumor cells and helping the immune system destroy the cancer. Imfinzi blocks PD-L1, a protein cancer cells use to evade the immune system. Imfinzi helps remove brakes on the immune response, while Imdelltra brings T cells directly to cancer cells and helps activate them to attack the tumor.

Imdelltra posted $288 million in sales during the second quarter, up 115% year over year, and generated $627 million in global sales in 2025, CNBC reported. The drug appears on its way to becoming a blockbuster medicine, or hitting the $1 billion sales threshold, the report said.