FDA Approves Subcutaneous Version of Merck's Keytruda
The U.S. Food and Drug Administration has approved Merck's Keytruda Qlex, a subcutaneous formulation of the cancer drug pembrolizumab, for use in adults across most solid tumor indications. Announced on September 19, 2025, this new injectable version offers a quicker administration time compared to the traditional intravenous method, potentially enhancing patient convenience and access to treatment. The approval highlights efforts to innovate drug delivery in oncology amid growing demands for efficient therapies.
Advancement in Immunotherapy Delivery
The U.S. Food and Drug Administration (FDA) approved Merck's Keytruda Qlex on September 19, 2025, introducing a subcutaneous injectable form of the widely used cancer immunotherapy pembrolizumab. This formulation combines pembrolizumab with berahyaluronidase alfa-pmph, enabling administration under the skin in as little as one minute, a significant reduction from the 30-minute intravenous infusions required for the original version. The decision applies to most adult solid tumor indications previously approved for Keytruda, with provisions for pediatric patients aged 12 and older in certain cases.
Merck's pursuit of this new delivery method stems from clinical data demonstrating equivalent efficacy and safety to the intravenous form. The approval is based on results from the KEYNOTE-A39 trial, which evaluated the subcutaneous version in patients with advanced cancers, showing comparable response rates and pharmacokinetic profiles. The FDA granted priority review status, expediting the process and reflecting the potential to address unmet needs in treatment administration, particularly for patients in settings where prolonged clinic visits pose challenges.
In a statement, Merck emphasized the convenience factor. "KEYTRUDA QLEX is the first and only subcutaneously administered immune checkpoint inhibitor that can be given by a health care provider in as little as one minute," the company noted in its announcement. This development aligns with broader trends in oncology to reduce treatment burdens, allowing patients more flexibility and potentially improving adherence to therapy regimens.
Keytruda, first approved in 2014, has become a cornerstone of cancer treatment, generating substantial revenue for Merck—over $20 billion annually in recent years. It functions as a PD-1 inhibitor, enhancing the immune system's ability to target cancer cells in indications such as melanoma, non-small cell lung cancer, head and neck squamous cell carcinoma, and others. The intravenous requirement has limited accessibility in some regions, including rural areas or during public health crises like the COVID-19 pandemic, where minimizing clinic time is crucial.
The subcutaneous option addresses these issues by enabling quicker injections, typically in a clinic setting, without the need for infusion equipment. Clinical trials reported a 45% response rate in non-small cell lung cancer patients, with adverse events similar to those of the intravenous form. Availability is expected in late September 2025, providing a rapid rollout to meet patient needs.
Medical experts have welcomed the approval while noting implementation considerations. Oncologists point out that while the shorter administration time could free up resources in busy clinics, training for healthcare providers on the new injector will be essential. Some sources, including Reuters, highlight that this formulation could help mitigate disparities in cancer care, especially for underserved populations facing barriers to infusion centers.
Economically, the approval comes as Keytruda's core patent protections approach expiration in 2028, potentially paving the way for biosimilars. By offering a patented subcutaneous version with protection through 2039, Merck aims to maintain market leadership in the $25 billion immunotherapy sector. Analysts project that this innovation could bolster sales amid increasing diagnoses of PD-L1-positive cancers.
On the regulatory front, the FDA's action follows positive recommendations from the European Medicines Agency's Committee for Medicinal Products for Human Use (CHMP) for a similar subcutaneous formulation, announced around the same time. The CHMP endorsed its use across all adult indications for Keytruda, with a decision from the European Commission expected in the fourth quarter of 2025. This transatlantic alignment underscores global efforts to standardize convenient treatment options.
Broader implications include potential shifts in oncology practices. Competitors like Bristol Myers Squibb and AstraZeneca are developing subcutaneous versions of their own PD-1 inhibitors, indicating an industry trend toward injection-based therapies. Environmental advocates have raised concerns about waste from single-use injectors, urging sustainable practices in packaging and disposal.
Policy-wise, this approval supports FDA initiatives to promote innovative drug deliveries, as seen in recent user fee agreements emphasizing efficiency and patient outcomes. In the U.S., where cancer disparities persist among minority and low-income groups, the subcutaneous option could enhance equity by enabling treatment in diverse settings.
However, challenges remain. Pricing details have not been fully disclosed, and insurance coverage will be key to ensuring broad access. Some experts caution that while the formulation is approved for most indications, ongoing trials may expand its use further. Globally, Merck plans to seek approvals in additional markets, potentially transforming cancer care in regions with limited infrastructure.
As Merck prepares for commercial launch, the focus will be on real-world outcomes. This approval not only extends the lifecycle of a blockbuster drug but also exemplifies how reformulations can integrate advanced therapies more seamlessly into patients' lives, balancing efficacy with practicality in the fight against cancer.