Belzutifan + Lenvatinib Improves PFS vs. Cabozantinib in Renal Cell Carcinoma

The landscape of treatment for advanced clear cell renal cell carcinoma (kidney cancer) has shifted with new data demonstrating a significant benefit from the combination of belzutifan and lenvatinib. Presented at the 2026 ASCO Genitourinary Cancers Symposium, the LITESPARK-011 trial showed that this combination markedly improved progression-free survival (PFS) compared to cabozantinib, a standard treatment for patients whose cancer has worsened after immunotherapy. This offers a potentially valuable new option for a challenging-to-treat population.

A New Combination for Advanced Kidney Cancer

For individuals with advanced renal cell carcinoma whose disease progresses despite initial treatment with immune checkpoint inhibitors, several options exist, including cabozantinib, lenvatinib plus everolimus, axitinib, tivozanib, and belzutifan. Although, until recently, there was limited evidence to suggest one treatment was definitively superior to another. The LITESPARK-011 trial aimed to address this gap, investigating whether combining belzutifan, an oral HIF-2alpha inhibitor approved for use after immunotherapy and VEGFR-TKI failure, with lenvatinib, a VEGFR-TKI, could offer improved outcomes.

The trial randomly assigned 747 patients with unresectable or metastatic clear cell renal cell carcinoma to receive either belzutifan (120 mg daily) plus lenvatinib (20 mg daily) or cabozantinib (60 mg daily). To be eligible, patients had to have experienced disease progression on or after first- or second-line anti-PD-L1 therapy, or within six months of completing adjuvant anti-PD-L1 therapy. The primary endpoints of the study were progression-free survival (PFS) and overall survival (OS), with objective response rate, duration of response, and safety as secondary endpoints.

The results were compelling. Patients receiving belzutifan plus lenvatinib experienced a 30% improvement in PFS (median of 14.8 months versus 10.7 months with cabozantinib; HR = 0.7, 95% CI, 0.59-0.84). Notably, at two years, 35.6% of patients in the belzutifan-lenvatinib arm remained progression-free, compared to just 19.1% in the cabozantinib arm. This suggests a durable benefit from the combination therapy.

Beyond PFS, the combination also demonstrated a significantly higher objective response rate (52.6% vs. 39.6%; P = .0002), including a more substantial complete response rate (5.4% vs. 1.1%). The median duration of response was also longer in the belzutifan-lenvatinib group (23 months vs. 12.3 months), with nearly half (49.5%) of patients maintaining their response at two years, compared to 25.5% in the cabozantinib arm. Healio provides a visual summary of these findings.

Understanding the Mechanism and Safety Profile

Belzutifan works by inhibiting HIF-2alpha, a protein that plays a role in tumor growth and blood vessel formation. Lenvatinib, is a VEGFR-TKI, targeting vascular endothelial growth factor receptors to disrupt blood supply to the tumor. Combining these two agents creates a dual blockade of angiogenesis, potentially leading to more effective tumor control. As Robert J. Motzer, MD, a genitourinary medical oncologist at Memorial Sloan Kettering Cancer Center, explained, there’s a strong rationale for this combination as they “block blood-vessel growth in tumors in different ways.”

While the combination showed promising efficacy, it’s critical to consider the safety profile. The belzutifan-lenvatinib arm experienced higher rates of anemia (69.2% vs. 25.6%), hypoxia (15.4% vs. 0%), and cardiac dysfunction (7% vs. 1.1%) compared to cabozantinib. However, rates of diarrhea (52.7% vs. 70.1%) and skin toxicity (20.5% vs. 51.2%) were lower. Importantly, the number of all-grade and high-grade adverse events were comparable between the two arms, and fewer patients had to discontinue treatment due to toxicity in the belzutifan-lenvatinib group.

Overall Survival and Future Directions

Although the combination of belzutifan and lenvatinib demonstrated a trend towards improved overall survival (median of 34.9 months vs. 27.6 months with cabozantinib), the difference did not reach statistical significance at the time of the initial analysis. Researchers plan to conduct a further analysis of overall survival data as it matures to provide a more definitive assessment of this endpoint.

Sumanta K. Pal, MD, FASCO, codirector of the kidney cancer program at City of Hope, acknowledged the safety trade-offs but emphasized the potential benefits of the combination, stating that the prolonged delay in cancer growth supports its consideration as a new treatment option. Healio reports on his statement.

What This Means for Patients

The LITESPARK-011 trial provides compelling evidence that belzutifan plus lenvatinib is an effective treatment option for patients with advanced clear cell renal cell carcinoma who have progressed after immunotherapy. The improved PFS and objective response rates, along with the durable responses observed, suggest that this combination could offer a significant clinical benefit. However, it’s crucial for patients to discuss the potential benefits and risks of this treatment with their oncologist to determine if it’s the right choice for their individual circumstances.

The findings from this trial are likely to influence clinical practice guidelines and treatment decisions for patients with advanced kidney cancer. Further research is ongoing to evaluate the long-term effects of belzutifan plus lenvatinib and to identify biomarkers that may predict which patients are most likely to benefit from this combination therapy. The next steps involve continued monitoring of overall survival data and exploration of potential predictive biomarkers to personalize treatment strategies.