FDA Approves Enfortumab Vedotin Plus Pembrolizumab for Perioperative Treatment of Muscle-Invasive Bladder Cancer
Key Insights
The FDA has approved enfortumab vedotin-ejfv (Padcev) combined with pembrolizumab (Keytruda) as perioperative therapy for muscle-invasive bladder cancer (search), marking a significant advancement for cisplatin-ineligible patients.
The KEYNOTE-905/EV-303 phase 3 trial demonstrated remarkable efficacy with a 57.1% pathological complete response rate and 60% reduction in risk of recurrence, progression, or death compared to surgery alone.
The combination therapy requires careful safety management due to grade 3 or higher adverse events occurring in 71.3% of patients, necessitating specialized pharmacist oversight for optimal implementation.
The FDA has approved enfortumab vedotin-ejfv (Padcev; Astellas Pharma Inc, Pfizer) combined with pembrolizumab (Keytruda; Merck (search)) for perioperative therapy in muscle-invasive bladder cancer (search) (MIBC), representing a significant advancement in treatment options for patients ineligible for cisplatin-based chemotherapy. This regimen consists of neoadjuvant therapy followed by radical cystectomy and subsequent adjuvant treatment, potentially redefining the standard of care for a vulnerable patient population.
Many patients with MIBC are considered cisplatin-ineligible due to comorbidities such as impaired renal or cardiac function or poor performance status, creating an urgent need for effective alternative treatments.
Landmark Clinical Trial Results
The efficacy supporting this approval comes from the KEYNOTE-905/EV-303 trial, a phase 3 study that demonstrated significant and clinically meaningful improvements when comparing the combination therapy to surgery alone. The regimen reduced the risk of recurrence, progression, or death by 60% and cut the risk of death by 50% compared to surgery alone.
The pathological complete response (pCR) rate observed with the perioperative combination was remarkably high at 57.1%, significantly surpassing the 8.6% rate seen with surgery alone. Both event-free survival and overall survival were also significantly improved. Median event-free survival was not reached versus 15.7 months, and median overall survival was not reached versus 41.7 months, when compared to the surgery-alone arm.
Safety Profile and Management Challenges
Although the clinical benefit is substantial, implementing this combination requires careful management due to its increased toxicity. Grade 3 or higher treatment-emergent adverse events (AEs) were reported in 71.3% of patients receiving enfortumab vedotin plus pembrolizumab, compared to 45.9% in the control arm. Notably, the perioperative combination did not negatively affect the ability of study participants to undergo surgery.
Key adverse events of special interest with enfortumab vedotin include skin reactions, peripheral neuropathy, ocular disorders, and hyperglycemia. Key adverse events associated with pembrolizumab include immune-related adverse events, particularly hypothyroidism and severe skin reactions.
Critical Role of Oncology Pharmacists
The successful use of perioperative enfortumab vedotin plus pembrolizumab depends heavily on the oncology pharmacist's expertise in three crucial areas: patient selection, treatment adherence, and advanced data integration.
Patient Selection and Risk Mitigation
Given the high rate of adverse events, the pharmacist's input is vital for appropriate patient selection. This treatment may not be suitable for all patients. For instance, patients with poorly controlled diabetes or severe peripheral neuropathy are likely not good candidates for enfortumab vedotin, while those with severe and active autoimmune conditions should probably not receive pembrolizumab. Pharmacists are instrumental in prescreening patients for these vulnerabilities and providing extensive counseling on managing potential adverse events.
Optimizing Treatment Continuity
The perioperative regimen spans neoadjuvant cycles, surgery, and subsequent adjuvant cycles. Ensuring continuity across these phases is a major challenge; in the EV-303 study, only 67% of patients who underwent cystectomy started the adjuvant phase. Pharmacists are critical in coordinating medication access and addressing practical barriers to maximize the rate of adjuvant therapy completion.
Integration of Emerging Biomarkers
The evolving landscape of MIBC treatment increasingly relies on biomarkers such as circulating tumor DNA (search) (ctDNA). The detection of postsurgical ctDNA positivity helps identify minimal residual disease and is associated with a higher probability of recurrence. As clinical trials begin to guide adjuvant treatment based on ctDNA status, pharmacists will be essential partners to the multidisciplinary team, aiding in the interpretation and application of these complex results to personalized treatment decisions.
The robust clinical data for enfortumab vedotin plus pembrolizumab offers a crucial therapeutic alternative for cisplatin-ineligible MIBC patients. Moving forward, the oncology pharmacist, through rigorous safety monitoring and strategic integration into the complex perioperative pathway, is central to ensuring that patients safely realize the full benefit of this combination.