Imfinzi plus Imjudo approved in EU for advanced cancers

AstraZeneca’s Imfinzi (durvalumab) and Imjudo (tremelimumab) immunotherapy combinations have been approved in the European Union (EU) for advanced liver and lung cancers.

The approvals authorise the dual immunotherapy for first-line treatment in adults with advanced or unresectable hepatocellular carcinoma (HCC) and Imfinzi in combination with Imjudo and platinum-based chemotherapy for adults with metastatic (Stage IV) non-small cell lung cancer (NSCLC).

EU approval of the immunotherapy combinations

The approvals by the European Commission (EC) follow positive recommendations by The Committee for Medicinal Products for Human Use (CHMP) in December 2022. Positive results from the HIMALAYA Phase III trial were published in the New England Journal of Medicine Evidence. Results from the POSEIDON Phase III trial were published in the Journal of Clinical Oncology.

Dr Solange Peters, PhD, Head of the Medical Oncology Service and Chair of Thoracic Oncology at Hospitalier Universitaire Vaudois, Lausanne, Switzerland, and principal investigator in the POSEIDON Phase III trial stated the EU approval means that patients in Europe “now have a valuable new treatment approach with demonstrated long-term survival benefits.”

The trials for Imfinzi with Imjudo

HIMALAYA Phase III trial

“In HIMALAYA, an estimated 31 percent of patients treated with this novel combination of tremelimumab with durvalumab were alive at three years, while only 20 percent of patients treated with sorafenib were still alive at the same duration of follow-up,” commented Dr Bruno Sangro, PhD, Director of the Liver Unit and Professor of Internal Medicine at Clínica Universidad de Navarra, and a lead investigator in the HIMALAYA Phase III trial.

A single dose of the anti-CTLA-4 antibody Imjudo (300mg) combined with anti-PD-L1 antibody Imfinzi (1500mg dose) was given to patients followed by Imfinzi every four weeks. The treatment significantly reduced the risk of death by 22 percent versus sorafenib. Median overall survival (OS) was 16.4 months versus 13.8 for sorafenib. An estimated 31 percent of patients treated with the combination were still alive after three years. A total of 20 percent of patients treated with sorafenib were still alive at the same duration of follow-up.

POSEIDON Phase III trial

The EU approval for metastatic NSCLC is based on results from the POSEIDON Phase III trial. The trial demonstrated that a limited course of five cycles of the anti-CTLA-4 antibody Imjudo added to Imfinzi, plus four cycles of platinum-based chemotherapy significantly reduced the risk of death by 23 percent versus a range of chemotherapy options.

Additional data on metastatic NSCLC in the POSEIDON Phase III trial showed:

• Median OS was 14.0 months versus 11.7 months for chemotherapy
• An estimated 33 percent of patients were alive at two years versus 22 percent for chemotherapy
• The risk of disease progression or death was reduced by 28 percent compared to chemotherapy alone with a median progression-free survival (PFS) of 6.2 months versus 4.8 months, respectively.

Updated results from a four-year follow-up of the trial showed:

• A sustained survival benefit, reducing the risk of death by 25 percent compared to only chemotherapy
• Median OS was 14 months for the combination versus 11.7 months for just chemotherapy
• An estimated 25 percent of patients treated with the combination were alive at three years versus 13.6 percent for those treated with chemotherapy alone.

The safety profile for Imjudo plus Imfinzi and chemotherapy in both trials was consistent with the known profiles of each medicine, and no new safety signals were identified.

For the POSEIDON indication in the EU, Imjudo will be temporarily marketed under the name Tremelimumab AstraZeneca until the second half of 2023.