Padcev and Keytruda combo cuts bladder cancer recurrence risk by 60% in pivotal Phase 3 win

Astellas Pharma Inc. and Pfizer Inc. have reported what could be a major clinical shift in the treatment of muscle-invasive bladder cancer, with new data from the Phase 3 EV-303 trial showing that a combination of Padcev and Keytruda, used before and after surgery, cut the risk of recurrence or death by 60% in cisplatin-ineligible patients. The trial, also known as KEYNOTE-905, was presented at the 2025 ESMO Congress and is now sparking momentum toward a potential new standard of care in a high-risk patient group long underserved by systemic therapies.

The study evaluated Padcev (enfortumab vedotin), a Nectin-4 targeting antibody-drug conjugate, in combination with the PD-1 inhibitor Keytruda (pembrolizumab) in patients with MIBC who are ineligible for or declined cisplatin-based chemotherapy. Data from the trial, presented at the 2025 European Society of Medical Oncology (ESMO) Congress in Berlin, indicate that the combination significantly improves both event-free survival (EFS) and overall survival (OS) when administered before and after surgery, compared to surgery alone. This outcome positions the Padcev–Keytruda regimen as a potential game-changer in a space long dominated by limited options for patients unfit for cisplatin therapy.

Muscle-invasive bladder cancer represents approximately 30% of all bladder cancer cases globally. The current standard of care involves cisplatin-based neoadjuvant chemotherapy followed by cystectomy. However, up to half of all MIBC patients are unable to tolerate cisplatin, often due to comorbidities or renal impairment, leaving surgery alone as their primary treatment route. This creates a significant treatment gap—one that the EV-303 trial now appears poised to fill with statistically and clinically significant results.

How significant were the survival gains reported in the EV-303 trial for Padcev and Keytruda?

According to the first interim efficacy analysis of the EV-303 trial, the combination therapy reduced the risk of tumor recurrence, progression, or death by 60% compared to surgery alone. The reported hazard ratio for EFS stood at 0.40 with a 95% confidence interval between 0.28 and 0.57, yielding a p-value of less than 0.0001. Median EFS had not been reached in the combination arm, while it was estimated at 15.7 months in the surgery-only arm. Two years after treatment, approximately 74.7% of patients who received the Padcev–Keytruda combination were event-free, compared to just 39.4% of those who underwent surgery alone.

In terms of overall survival, the risk of death was halved for those receiving the combination, with a hazard ratio of 0.50 and a 95% confidence interval of 0.33 to 0.74. The median overall survival had not been reached in the Padcev–Keytruda arm but was pegged at 41.7 months in the control group. At the two-year mark, 79.7% of patients treated with the combination were still alive, in contrast to 63.1% for the surgery-only cohort.

Consistent benefits were observed across all predefined subgroups, including age, gender, PD-L1 expression, smoking history, and geographical region. These across-the-board gains reinforce the potential broad applicability of the combination therapy in real-world settings and across diverse patient populations.

Why could this combination redefine the standard of care for cisplatin-ineligible bladder cancer?

For decades, patients with MIBC who cannot receive cisplatin-based chemotherapy have faced limited treatment choices and often poor prognoses. Surgery alone typically results in suboptimal long-term outcomes. The EV-303 trial not only offers survival benefits but also introduces the first systemic treatment to demonstrate a survival advantage in the perioperative setting—before and after surgery—for this high-risk group. The pathologic complete response (pCR) rate in the neoadjuvant setting reached 57.1% for patients receiving the Padcev–Keytruda combo, versus just 8.6% in the surgery-only arm, representing a near sevenfold improvement.

These results, viewed as groundbreaking by leading oncologists, suggest that this combination could become the new benchmark for treatment efficacy in cisplatin-ineligible patients. The benefits are not just statistically compelling but also potentially transformative in improving patient quality of life and long-term outcomes. Regulatory filings are now expected to follow, marking a critical next step toward formal approval and integration into standard treatment guidelines.

What are the expert and institutional reactions to the Padcev–Keytruda survival data?

Oncology specialists and institutional investors alike have responded to the data with cautious optimism. The 60% reduction in EFS events and the 50% improvement in OS are seen as compelling markers of the regimen’s efficacy. While official analyst commentary has not been widely circulated, the consensus forming in institutional discussions is one of bullish sentiment. The results are being viewed as a potential growth lever for both Astellas Pharma Inc. and Pfizer Inc., particularly if regulatory approvals open the door to broader commercial applications across multiple geographies.

While not all experts are prepared to declare it a new standard of care just yet, the sentiment is largely positive. Clinicians have highlighted the unprecedented efficacy signals in a patient segment historically underserved by systemic therapies. If ongoing trials and real-world studies continue to confirm the benefit–risk profile, it is expected that clinical practice could shift rapidly.

How soon could regulatory approvals and global filings turn Padcev plus Keytruda into a new standard of care for bladder cancer?

The Padcev and Keytruda combination is not currently approved for use as a perioperative therapy in patients with muscle-invasive bladder cancer. However, Astellas and Pfizer have indicated their intention to engage with global regulatory bodies for potential label expansion based on the EV-303 results. In parallel, a second Phase 3 trial—EV-304 (KEYNOTE-B15)—is evaluating the combination in cisplatin-eligible patients, signaling further efforts to expand the regimen’s applicability.

If approved, the combination could see rapid adoption, particularly given the limited treatment options currently available for cisplatin-ineligible patients. Payers and healthcare systems are likely to scrutinize cost-effectiveness and long-term outcomes, but the magnitude of clinical benefit seen so far provides a strong foundation for reimbursement discussions.

Institutionally, investor attention will likely shift to monitoring regulatory milestones, future trial readouts, and the competitive landscape, particularly with other immunotherapy and antibody-drug conjugate pipelines maturing in parallel. The combination of a targeted ADC with a checkpoint inhibitor is also being seen as a strategic blueprint for similar regimens in other tumor types.

How will the safety profile and tolerability of the Padcev–Keytruda combination influence its long‑term use in real‑world bladder cancer care?

Safety remains a critical aspect of any perioperative therapy. In the EV-303 trial, the safety profile of the Padcev–Keytruda combination was consistent with known adverse events from prior studies. The most frequently reported side effects included pruritus, alopecia, diarrhea, fatigue, and anemia. Grade 3 or higher adverse events were observed in 71.3% of patients receiving the combination, compared to 45.9% in the surgery-only group.

While this adverse event rate may raise concerns about tolerability, especially in a frail population, the lack of new safety signals and the substantial survival benefits may outweigh these risks in the eyes of clinicians and patients. However, post-marketing safety data and real-world monitoring will be crucial to understanding how the combination performs outside the controlled environment of a clinical trial.

How could the Padcev and Keytruda breakthrough reshape outcomes and reduce the global disease burden of muscle‑invasive bladder cancer?

Bladder cancer ranks as the ninth most commonly diagnosed cancer globally, with more than 614,000 new cases annually. Muscle-invasive bladder cancer comprises roughly 30% of those cases and is often associated with high rates of recurrence and mortality, especially among patients who cannot tolerate standard cisplatin-based regimens. By potentially offering a superior treatment path, the Padcev and Keytruda combination could help improve survival rates and reduce the global disease burden.

Given the momentum of immuno-oncology in other cancers like lung, melanoma, and head and neck, the bladder cancer landscape has lagged behind. This trial outcome marks a clear shift, with the potential for immune-based regimens to become foundational even in earlier stages of disease—not just metastatic settings.

What are the most important clinical and strategic takeaways from the EV-303 trial results?

• The Phase 3 EV-303 (KEYNOTE-905) trial demonstrated that Padcev (enfortumab vedotin) plus Keytruda (pembrolizumab), when used both before and after surgery, reduced the risk of recurrence, progression, or death by 60% in cisplatin-ineligible patients with muscle-invasive bladder cancer.
• The combination therapy also reduced the risk of death by 50% versus surgery alone, with two-year survival rates of nearly 80% in the treatment arm compared to 63.1% with surgery only.
• The Padcev–Keytruda combination achieved a pathologic complete response (pCR) rate of 57.1%, far exceeding the 8.6% pCR seen in the surgery-only group.
• Benefits were consistent across age, gender, smoking status, PD-L1 status, clinical stage, and geographic regions, indicating broad applicability.
• Safety signals remained consistent with known profiles of both drugs, though grade ≥3 adverse events were more frequent in the combination group (71.3% vs. 45.9%).
• Astellas Pharma Inc. and Pfizer Inc. plan to engage with global regulators for potential approval, with follow-on data expected from the EV-304 trial in cisplatin-eligible patients.
• Analysts view the trial results as a potential catalyst for redefining the standard of care in perioperative bladder cancer treatment, particularly in an underserved patient segment.
• If approved, the regimen could open new market opportunities and strengthen the oncology portfolios of both companies through a broader immunotherapy-ADC treatment model.