Sugemalimab Shows Prolonged PFS in Stage III NSCLC

Gina Mauro
Gina Mauro

Editorial Director, OncLive
Gina Mauro is your lead editorial contact for OncLive. She joined the company in 2015 and has held various positions on OncLive; she is also the on-air correspondent for OncLive News Network: On Location. Prior to joining MJH Life Sciences, she worked at Gannett as a full-time reporter with the Asbury Park Press. Email: 

The investigational PD-L1 inhibitor sugemalimab prolonged progression-free survival in patients with locally advanced, unresectable stage III non–small cell lung cancer without disease progression after concurrent or sequential chemoradiation.

The investigational PD-L1 inhibitor sugemalimab prolonged progression-free survival (PFS) in patients with locally advanced, unresectable stage III non–small cell lung cancer (NSCLC) without disease progression after concurrent or sequential chemoradiation, according to a planned interim analysis of the phase 3 GEMSTONE-301 trial (NCT03728556).1

A Blinded Independent Central Review (BICR) via RECIST v1.1 criteria determined the efficacy with sugemalimab, which was found to be statistically improvement and clinically meaningful. Clinical benefit was observed irrespective of whether patients received concurrent or sequential CRT prior to undergoing treatment with the PD-L1 agent.

The agent was also found to be well tolerated, and no new safety signals were observed in prespecified subgroups. Full findings of GEMSTONE-301 will be presented at an upcoming medical meeting.

“Stage III NSCLC represents a heterogeneous group of patients with a wide range of therapeutic outcomes. Around the world, both sequential and concurrent chemotherapy are commonly used treatment approaches for this stage of disease,” said Vincent Miller, MD, physician-in-chief at EQRx, which partners with CStone Pharmaceuticals. “These encouraging results from both the stage III and stage IV studies suggest sugemalimab is a promising potential treatment option in a broad range of patient populations.”

The China National Medical Products Administration accepted a new drug application for sugemalimab combined with chemotherapy in November 2020 for the frontline treatment of patients with advanced squamous and nonsquamous NSCLC.

In the Chinese, multicenter, randomized, double-blind GEMSTONE-301 trial, investigators are evaluating the efficacy and safety of sugemalimab as consolidation treatment in patients with locally advanced/unresectable stage III NSCLC who did not have disease progression following concurrent or sequential CRT. The primary end point is PFS, as assessed by BICR according to RECIST v1.1 criteria, while secondary end points are overall survival (OS), investigator-assessed PFS, and safety.

Previously, sugemalimab highlighted efficacy in combination with standard platinum-based chemotherapy in patients with treatment-naïve stage IV nonsquamous or squamous NSCLC, regardless of the level of PD-L1 expression, and was also found to be well tolerated.2 The benefit was seen in the phase 3, double-blind GEMSTONE-302 trial (NCT03789604), which was also conducted in China with a primary end point of investigator-assessed PFS. Secondary end points were OS, BICR-assessed PFS, and safety.

Specifically, the interim data showed a 50% reduction in the risk of disease progression or death with sugemalimab/chemotherapy vs placebo plus chemotherapy, and the benefit was seen regardless of PD-L1 expression level or pathologic subtype. The median PFS was 7.82 months (95% CI, 6.90-8.97) with sugemalimab vs 4.90 months (95% CI, 4.70-5.03) in the placebo/chemotherapy arm (HR, 0.50; 95% CI, 0.39-0.64; P < .0001).

“The PD-1/PD-L1 market is becoming more crowded, but the constant debate around pricing without action is to the detriment of patients. EQRx was created to address this challenge head-on by bringing high-quality medicines to patients at much lower prices,” commented Alexis Borisy, chief executive officer of EQRx. “PD(L)1 therapies are the backbone of cancer treatment, and we see tremendous opportunity for sugemalimab as a monotherapy or in combination regimens, lowering the overall costs of immunotherapy options.”

Sugemalimab is also being explored in a single-arm, phase 2 trial (NCT03595657) as a single agent for the treatment of adult patients with relapsed/refractory extranodal natural killer/T-cell lymphoma (ENKTL). The FDA previously granted the agent orphan drug designation as a T-cell lymphoma treatment and a breakthrough therapy designation for relapsed/refractory ENKTL treatment.


  1. Primary endpoint met in phase 3 study of the anti-PD-L1 antibody sugemalimab in stage III non-small cell lung cancer. News release. EQRx. May 28, 2021. Accessed May 28, 2021.
  2. Zhou C, Wang Z, Sun Y, et al. GEMSTONE-302: randomized double-blind, phase 3 study of sugemalimab or placebo plus platinum-based chemotherapy as first-line treatment for metastatic NSCLC. Ann Oncol. 2020;31(suppl_6):S1386-S1406. doi:10.1016/annonc/annonc367