Imfinzi Combo Therapy Extends Survival of Advanced SCLC Patients, Phase 3 Trial Shows

Adding Imfinzi (durvalumab) to standard first-line chemotherapy led to a clinically meaningful extension in the overall survival of patients with advanced small cell lung cancer (SCLC), according to results of a Phase 3 clinical trial.

The open-label, global CASPIAN trial (NCT03043872) is testing AstraZeneca’s Imfinzi combined with chemotherapies — etoposide and either cisplatin or carboplatin — or Imfinzi with tremelimumab and chemotherapy, compared with chemotherapy alone in patients with extensive-stage SCLC, meaning the cancer has spread to the lungs or other parts of the body.

Patients received up to four cycles of chemotherapy, while those in the control group had up to six cycles of chemotherapy and prophylactic cranial irradiation — a radiation therapy to kill tumor cells.

Safety and tolerability of the Imfinzi combination approach was in line with the known safety profiles of the different medicines. AstraZeneca is planning to present these results at an upcoming medical meeting.

CASPIAN is being conducted in more than 200 centers in 22 countries, including the U.S., Europe, South America, Asia, and the Middle East. The final analysis will assess the benefits of combining Imfinzi, tremelimumab, and chemotherapy.

“The Phase III CASPIAN results offer new hope for patients … for whom new medicines are urgently needed,” José Baselga, AstraZeneca’s executive vice president, oncology research and development, said in a press release. “This is the first trial offering the flexibility of combining immunotherapy with different platinum-based regimens in small cell lung cancer, expanding treatment options.”

Both Imfinzi and the investigational medicine tremelimumab belong to a type of cancer antibody treatment called immune checkpoint inhibitors. While Imfinzi targets the PD-L1 protein on cancer cells, tremelimumab selectively binds to the CTLA-4 protein on T-cells. By binding to their targets, both therapies are intended to block mechanisms used by cancer to evade immune attack and boost the body’s anti-tumor response.

Besides CASPIAN, Imfinzi is also being assessed following chemoradiation therapy in limited-stage SCLC in the multicenter Phase 3 ADRIATIC trial (NCT03703297), which is still enrolling patients.

Based on results of the Phase 3 PACIFIC trial (NCT02125461), treatment with Imfinzi has been approved for advanced (stage 3) non-small cell lung cancer — the most common type of lung cancer — in more than 45 countries, including the U.S., EU, and Japan.

The therapy is also approved for previously treated patients with advanced bladder cancer in several countries, including the U.S., Canada, and Australia.

Imfinzi is being evaluated as a stand-alone therapy or in combination with tremelimumab and/or chemotherapy in Phase 3 trials of small and non-small cell lung cancer, bladder cancer, liver cancer, head and neck cancer, cervical cancer, and biliary tract cancer, as well as other solid blood cancers.