Results from a new study demonstrate that consolidation therapy - or treatment given for a short time after the initial treatment has stopped cancer growth - after chemoradiotherapy with durvalumab helps patients with limited-stage small-cell lung cancer (LS-SCLC) live longer when compared to the current standard-of-care treatment of chemoradiotherapy alone.

The research was presented at the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting, taking place May 31-June 4 in Chicago, Illinois.

“We have seen advances with immunotherapy in locally advanced unresectable and metastatic non-small-cell lung cancer (NSCLC) and more recently in early-stage resectable NSCLC. We’ve also seen advances in extensive, or metastatic, SCLC. This is the first trial to show that immunotherapy helps patients with limited-stage, or non-metastatic, SCLC,” said lead study author David R. Spigel, MD, Chief Scientific Officer, Sarah Cannon Research Institute, Nashville, Tennessee.

This interim analysis of the phase III ADRIATIC trial compares the outcomes in patients assigned to receive durvalumab (264 patients) with patients who received a placebo (266 patients).

All patients had completed chemoradiotherapy within the previous 42 days.

Some participants also received radiation therapy directly to the head, called prophylactic cranial irradiation, to reduce the progression of cancer in the brain.

Key Findings

As of January 15, 2024, the median overall survival was approximately 56 months in the patients who received durvalumab and 33 months in the patients who received a placebo. 

The median progression-free survival (PFS) was about 17 months for patients who received durvalumab compared to 9 months for patients who received the placebo.

The 36-month OS rate was approximately 57% in the durvalumab group and 48% in the placebo group.

The 24-month PFS rate was about 46% in the durvalumab group and 34% in the placebo group. 

The rate of severe side effects was the same in both groups (24%).

About 16% of the participants in the durvalumab group stopped treatment because of side effects compared to 11% in the placebo group.

About 38% of participants in the durvalumab group developed pneumonitis, a known side effect of these radiation and immunotherapy treatment, compared to 30% in the placebo group.

The rate of severe pneumonitis, which is considered grade 3 or 4, was similar between the two groups (3.0% in the durvalumab group and 2.6% in the placebo group). 

“The standard treatment for patients with Limited Stage Small Cell Lung Cancer (SCLC) has not changed significantly since the 1980’s. In this trial, patients with this cancer who received the addition of immunotherapy after traditional chemotherapy and radiation lived longer and were less likely to have their cancer recur.” – Lauren Byers, MD, Professor and Thoracic Section Chief in the Department of Thoracic/Head and Neck Medical Oncology at MD Anderson Cancer Center.

Next Steps

Researchers will continue to follow the study participants to evaluate if there are better results in patients who take a combination of durvalumab and tremelimumab.

They will also analyse different subsets to determine if there are any groups of patients with LS-SCLC that have better outcomes on these drugs.

Source: ASCO