Subcutaneous Toripalimab Achieves Pharmacokinetic Noninferiority in NSCLC

A phase 3 clinical study (NCT06505837) evaluating a subcutaneous (SC) formulation of the PD-1 inhibitor toripalimab (Loqtorzi), JS001sc, has successfully demonstrated noninferior drug exposure compared to the established intravenous (IV) formulation, JS001, in patients with recurrent or metastatic nonsquamous non–small cell lung cancer (NSCLC).¹ This finding supports a significant clinical pathway shift, prioritizing patient convenience and accessibility in the administration of cancer immunotherapy (I-O) agents.

The study, designated JS001sc-002-III-NSCLC, confirmed that the pharmacokinetics (PK) of the SC injection were noninferior to the IV infusion when used in combination with chemotherapy as a first-line treatment regimen. Furthermore, the 2 formulations exhibited comparable efficacy and safety profiles across the trial population, indicating that the subcutaneous delivery method maintained the therapeutic integrity of the established PD-1 inhibitor.

The success of this multicenter, open-label, randomized trial represents a pivotal advancement for toripalimab, which was China's first domestically developed anti–PD-1 monoclonal antibody. Following these positive results, Junshi Biosciences, the developer, plans to submit a new drug application (NDA) to regulatory authorities, seeking approval for the SC formulation across all indications currently approved for the IV toripalimab.

Addressing the Unmet Need for Convenient Administration

The shift toward a subcutaneous option is a direct response to a significant, yet often overlooked, clinical need within oncology: the burden associated with repeated intravenous drug administration. While I-O therapy with anti–PD-1 antibodies has become a cornerstone of standard-of-care across various cancer stages, the traditional IV method presents several challenges: it requires lengthy infusion times, necessitates frequent venous access, and places a considerable demand on outpatient medical resources and infusion center capacity.

The SC formulation directly addresses these inconveniences, simplifying procedures for both patients and health care systems. For patients, shorter administration times translate to less time spent in the clinic, reduced stress associated with IV catheterization, and an enhanced quality of life during treatment. As Jianjun Zou, MD, general manager and CEO of Junshi Biosciences, noted, this innovation marks a "pivotal breakthrough in transitioning I-O therapy from 'efficacy' to 'convenience'," thereby enhancing treatment accessibility and reducing the overall healthcare burden.

Context of Disease Burden

The clinical significance of this development is underscored by the high prevalence of lung cancer. NSCLC accounts for approximately 85% of all lung cancer diagnoses, with the nonsquamous subtype constituting about 65% of those cases. Data from GLOBOCAN 2022 highlights the critical impact of this disease in China, where the study was conducted, estimating 1.06 million new lung cancer cases and 0.73 million lung cancer deaths, accounting for 22.0% of total new cancers and 28.5% of total cancer deaths, respectively. Providing a simpler administration route for a key treatment like toripalimab, which is approved for 12 indications globally and used in over 40 countries, holds the potential to impact a substantial patient population.

The JS001sc-002-III-NSCLC study was strategically designed as a noninferiority trial to establish the equivalence of the SC formulation to the established IV product.² Noninferiority in drug exposure (PK) was the foundational primary end point. Secondary end points included overall response rate, progression-free survival, disease control rate, duration of response, and safety.

REFERENCES

1. Junshi Biosciences announces primary endpoints met in JS001sc’s phase 3 study for the 1st-line treatment of NSQ-NSCLC. News release. Junshi Biosciences. November 25, 2025. Accessed November 25, 2025. https://tinyurl.com/5d2dyc2x

2. JS001sc or JS001 plus chemotherapy is indicated for relapsed or metastatic first-line non-squamous non small cell lung cancer（NSCLC). ClinicalTrials.gov. Updated August 28, 2025. Accessed November 25, 2025. https://clinicaltrials.gov/study/NCT06505837