Belzutifan Shows Sustained Efficacy in Heavily Pretreated Clear Cell Renal Cell Carcinoma Patients

Belzutifan查看药品详情 (Welireg查看药品详情) maintained its therapeutic advantage over everolimus查看药品详情 (Afinitor查看药品详情) in patients with heavily pretreated clear cell renal cell carcinoma (搜索)搜索该疾病 (ccRCC (搜索)搜索该疾病), according to an exploratory analysis of the LITESPARK-005 trial presented at the 2025 ESMO Congress. The analysis focused on patients who had received at least one anti-PD-(L)1 therapy and at least two VEGFR (搜索)搜索该靶点 TKIs, representing a challenging population with limited treatment options.

Efficacy Results in Heavily Pretreated Population

In the subgroup of patients who received at least two prior VEGFR (搜索)搜索该靶点 TKIs, belzutifan查看药品详情 (n = 187) achieved a median progression-free survival (PFS) of 4.6 months (95% CI, 3.5-7.3) compared to 5.4 months (95% CI, 3.8-6.5) with everolimus查看药品详情 (n = 182), representing a hazard ratio of 0.73 (95% CI, 0.57-0.94). The median overall survival values were 21.8 months (95% CI, 17.4-25.8) and 18.1 months (95% CI, 14.2-23.9), respectively (HR, 0.94; 95% CI, 0.74-1.21).

The overall response rates per RECIST 1.1 criteria showed a striking difference between treatment arms. Belzutifan查看药品详情 achieved a 24.1% overall response rate (95% CI, 18.1%-30.8%) compared to 3.3% (95% CI, 1.2%-7.0%) with everolimus查看药品详情, representing an estimated difference of 20.8% (95% CI, 14.3%-27.7%). Notably, five patients who received belzutifan achieved complete responses, while no patients in the everolimus arm did so.

The median duration of response values were 17.5 months (95% CI, 1.9+ to 39.8+) for belzutifan查看药品详情 and 10.9 months (95% CI, 3.8-28.4+) for everolimus查看药品详情. The median times to response were 3.7 months (range, 1.7-22.0) and 3.0 months (range, 1.8-5.4), respectively.

Study Design and Patient Characteristics

LITESPARK-005 enrolled patients with unresectable, locally advanced or metastatic ccRCC (搜索)搜索该疾病 who experienced disease progression following one to three prior lines of therapy. Prior treatments needed to include at least one anti-PD(L)1 monoclonal antibody and at least one VEGFR (搜索)搜索该靶点 TKI. Patients were required to have a Karnofsky Performance Status score of at least 70%.

Patients were randomly assigned 1:1 to receive either 120 mg of belzutifan查看药品详情 or 10 mg of everolimus查看药品详情, both administered as once-daily oral doses. Stratification occurred based on International Metastatic RCC Database Consortium (IMDC) prognostic score and the number of prior VEGFR (搜索)搜索该靶点-targeted therapies.

At baseline, patients in the belzutifan查看药品详情 subgroup who were treated with at least two prior VEGFR (搜索)搜索该靶点 TKIs had a median age of 62.0 years (range, 40-81). Most patients were male (79.1%), had a Karnofsky Performance Status score of 90 or 100 (62.0%), had IMDC intermediate-risk disease (65.2%), and received three or four prior lines of therapy (85.6%).

Safety Profile and Clinical Management

The safety profile in the subgroup analysis remained consistent with the overall trial population. Patients who received belzutifan查看药品详情 (n = 186) or everolimus查看药品详情 (n = 177) experienced any-grade adverse effects at respective rates of 99.5% and 98.9%. Grade 3 or higher adverse events occurred in 66.1% versus 59.3% of patients, serious adverse events in 44.6% versus 39.0%, and adverse events leading to dose reduction in 15.6% versus 13.6%, dose discontinuation in 7.0% versus 14.1%, or death in 5.4% versus 4.5%.

Clinical Experience and Toxicity Management

According to Sumanta K. Pal, MD, FASCO, professor at City of Hope (搜索)搜索该词条, "There is no doubt in my mind that belzutifan查看药品详情 is a well-tolerated drug. The main toxicities that we tend to look for are anemia (搜索)搜索该疾病 and hypoxia (搜索)搜索该疾病." He recommends that patients purchase a pulse oximeter and maintain a log of readings, advising them to stop the drug if oxygen saturation falls below 92%.

Dr. Pal noted that anemia (搜索)搜索该疾病 presents a particular challenge in the late-line setting: "A patient who is on third- or fourth-line therapy usually has a hemoglobin reading from 12 to 16 g/dL. It's typically going to dip down to a range of 8 to 10 g/dL. With belzutifan查看药品详情, you'll almost immediately see a dip in hemoglobin levels."

For managing hypoxia (搜索)搜索该疾病 in patients already requiring oxygen support, Dr. Pal suggests close monitoring with weekly oxygen value submissions and dose reductions from 120 mg to 80 mg or even 40 mg if necessary. "There is a possibility that at those lower doses you can avoid the effect of de-oxygenation," he explained.

Treatment Sequencing Considerations

Clinical experts discussed the positioning of belzutifan查看药品详情 in treatment algorithms. Dr. Rafid Kouz shared his experience with a heavily pretreated patient: "I ended up giving them belzutifan as a last resort, after treating with immunotherapy and tyrosine kinase inhibitor, followed by tivozanib查看药品详情. Interestingly, the patient has been doing well on [belzutifan] with a very good response rate."

The drug's approval by the FDA in December 2023 was supported by the LITESPARK-005 data for patients with advanced RCC (搜索)搜索该疾病 following treatment with a PD-1 (搜索)搜索该靶点 or PD-L1 (搜索)搜索该靶点 inhibitor and a VEGF (搜索)搜索该靶点 TKI, establishing its role in the treatment landscape for heavily pretreated patients.