Putting CAMEL-sq into perspective
Data from other trials of immunotherapy-chemotherapy combinations in squamous NSCLC have been presented recently but with less impressive results, Dr. Brahmer said.
In one trial – ORIENT-12 – sintilimab was combined with gemcitabine and cisplatin (ESMO 2020, Abstract LBA56). The median PFS, per investigators, was 5.5 months with sintilimab and 4.9 months without it, both of which are lower than the 8.5 months seen with camrelizumab plus chemotherapy in the CAMEL-sq trial.
Another trial is KEYNOTE-407, in which patients received pembrolizumab or placebo plus a carboplatin-paclitaxel (or nab-paclitaxel) regimen. Three-year follow-up data from the trial were presented at ELCC 2021 (Abstract 97O). Continued improvements in second PFS (HR, 0.59) and OS (HR, 0.71) were observed with pembrolizumab-chemotherapy versus placebo-chemotherapy.
“We have to remember the high PD-L1-negative disease rate in the CAMEL-sq study, compared to the KEYNOTE-407 rate,” before stacking the two studies against each other, Dr. Brahmer noted. In KEYNOTE-407, almost 35% of patients had PD-L1 expression of less than 1%, compared with nearly 50% in the CAMEL-sq study.
That aside, “very similar impressive 1-year progression-free survival rates are seen on both studies,” Dr. Brahmer said. “I hope that camrelizumab has continued follow-up so we can see how these patients will do long-term.
“My eyebrows were raised a little bit at the camrelizumab immune-related AE rate of almost 76%, compared to the immune-related AE rate of about 36% in the KEYNOTE-407 study,” Dr. Brahmer said.
She noted, however, that almost two-thirds of the immune-related AEs in CAMEL-sq were due to reactive cutaneous capillary endothelial proliferation, which doesn’t appear to have been previously reported with PD-1 or PD-L1 inhibitors. This is a side effect seen in studies of liver cancer and may be linked to PFS, Dr. Brahmer said.
CAMEL-sq is funded by Jiangsu Hengrui Medicine Co. Ltd. Dr. Zhou disclosed honoraria from multiple pharmaceutical companies, including the study sponsor. Two of Dr. Zhou’s coauthors are employees of the company. Dr. Brahmer disclosed relationships with Amgen, Bristol Myers Squibb, Eli Lily, GlaxoSmithKline, Merck, Sanofi, Easi, AstraZeneca, Genentech, Regeneron, and RAPT Therapeutics Inc.
