Rahway, N.J., Nov. 21, 2025 — In a major advancement for oncology treatment, the U.S. Food and Drug Administration (FDA) has approved KEYTRUDA® (pembrolizumab) and the newly introduced KEYTRUDA QLEX™ (pembrolizumab and berahyaluronidase alfa-pmph), each in combination with Padcev® (enfortumab vedotin-ejfv), as a perioperative treatment for adults with cisplatin-ineligible muscle-invasive bladder cancer (MIBC). This marks the first-ever PD-1 inhibitor plus ADC perioperative regimen available for this high-risk patient population, expanding options for individuals unable to tolerate traditional cisplatin-based chemotherapy
Science Significance
This approval represents a scientific milestone, as it validates a novel immunotherapy-plus-antibody-drug-conjugate (ADC) approach in early-stage bladder cancer. Data from the Phase 3 KEYNOTE-905 (EV-303) trial demonstrated a 60% reduction in event-free survival risk and a 50% improvement in overall survival for patients receiving the combination therapy compared with surgery alone, with pathologic complete response patterns strongly favoring the immunotherapy-ADC regimen. The introduction of KEYTRUDA QLEX, enabling subcutaneous administration, further expands scientific innovation by optimizing delivery while maintaining pharmacokinetic equivalence to intravenous pembrolizumab. These results highlight the therapeutic potential of integrated immuno-oncology and ADC platforms in reshaping cancer treatment.
Regulatory Significance
The FDA’s decision underscores confidence in robust clinical evidence and reflects significant progress in regulating immune-based perioperative therapies. This clearance establishes a new regulatory pathway for PD-1 inhibitors combined with ADCs as standard options in earlier-stage solid tumors. KEYTRUDA and its QLEX formulation demonstrated consistent safety, immune-mediated toxicity profiles, and manufacturing reliability aligned with GxP standards. For regulators, this approval may shape future considerations for combination regimens, multi-phase treatment designs, and acceptance of alternative delivery formats such as subcutaneous biologics, especially when equivalence and patient-centric benefits are well documented in pivotal datasets
Business Significance
Advertisement
For Merck, the approval strengthens the company’s market leadership in immuno-oncology, expanding the KEYTRUDA franchise into perioperative settings not previously accessible. The success of KEYNOTE-905, conducted in collaboration with Pfizer and Astellas, reinforces the commercial and strategic value of cross-company R&D partnerships in high-growth oncology segments. The addition of KEYTRUDA QLEX also introduces administration flexibility, potentially increasing treatment adoption in both hospital and outpatient settings. As the first PD-1 plus ADC perioperative regimen for cisplatin-ineligible MIBC, this approval is expected to create substantial business momentum and influence future market dynamics across urologic oncology therapeutics.
Patients’ Significance
For patients with MIBC who cannot receive cisplatin — a population representing a large clinical gap — the newly approved regimens offer meaningful survival benefits and an urgently needed alternative to surgery alone. Many patients face high recurrence rates even after bladder removal surgery, and having access to a proven perioperative immunotherapy-ADC combination significantly enhances the opportunity for durable outcomes. Moreover, the introduction of subcutaneous KEYTRUDA QLEX empowers clinicians to provide faster, more convenient administration, improving treatment accessibility and supporting patient comfort without compromising efficacy or safety
Policy Significance
From a health-policy perspective, this FDA approval demonstrates the increasing importance of supporting innovative multimodal oncology regimens and underscores the evolving policy environment prioritizing treatment accessibility for chemotherapy-ineligible populations. It also highlights the need for reimbursement frameworks that address subcutaneous biologic formulations, which may reduce clinic burden and improve throughput. As cancer-care guidelines evolve, this decision is likely to influence future policy updates in urologic cancer management, perioperative immunotherapy integration, and national quality-of-care standards.
Overall, the FDA’s approval of KEYTRUDA, KEYTRUDA QLEX, and Padcev as perioperative options for cisplatin-ineligible muscle-invasive bladder cancer marks a transformative advancement in oncology care. Supported by compelling survival and response data, the decision signals progress in integrating immune-oncology and ADC technologies into earlier treatment phases. This milestone stands to reshape clinical practice, strengthen regulatory confidence in combination regimens, and ultimately broaden life-extending options for patients with limited therapeutic alternatives.
Source: Merck press release
