The Food and Drug Administration (FDA) recently approved Welireg (belzutifan) for patients with advanced renal cell carcinoma (RCC) who experienced progression after receiving a PD-1 and/or PD-L1 checkpoint inhibitor, and a vascular endothelial growth factor tyrosine kinase inhibitor (VEGF-TKI).
According to the National Cancer Institute, Welireg is a type of drug that blocks specific proteins, which can help destroy tumors. The drug may also help prevent new blood vessels from growing, which tumors need in order to survive.
This FDA approval arrived following results from the LITESPARK-005 trial, which compared the objective response rates (patients who had a partial or complete response to treatment) of Welireg and Afinitor (everolimus). The trial analyzed these two drugs in patients with advanced RCC, which is the most common type of kidney cancer, according to the American Cancer Society.
Hilz received a diagnosis of stage 4 RCC in 2015 and was told there were tumors on his kidney and adrenal gland, which also spread to his lungs. Even after several treatments, including radiation, surgery, the removal of his left kidney and adrenal glands, and treatment with Avastin (bevacizumab) that he said was discontinued due to side effects, Hilz was still left with more than 30 present tumors throughout his body.
“(For) my first treatment (of Welireg), I was only on for 70 days, but I actually started having tumor reductions (before the) 90-day period in between scans,” Hilz said. “Plus, it stopped all tumor growth everywhere else. I had additional tumor reductions on my next 90-day scan, and then completely stable everywhere else.
“After eight years of not finding anything from a systemic therapy that would work, having this available for you is (a) pretty good deal. And also, to think (Welireg) was not even available when I had the initial cancer, to be looking for a systemic therapy that showed some promise for me for eight years, being stage four, and then finally finding something — especially when you’re aware you’re starting to really run out of options, it has been a wonderful lifesaver for me.”
Trial findings, which were presented earlier this year at the European Society of Medical Oncology Annual Congress (ESMO), showed that at a median follow-up of 18.4 months, patients treated with Welireg experienced objective response rates of 21.9% compared with 3.5% among patients treated with Afinitor, and 12-month progression-free survival (PFS; the time a patient lives without their disease spreading or worsening) rates of 33.7% on Welireg versus 17.6% with Afinitor, and 18-month PFS rates of 22.5% and 9%, respectively.
The most common side effects of Welireg, occurring in at least 25% of patients, included decreased hemoglobin, fatigue, musculoskeletal pain, increased creatinine, decreased lymphocytes, increased alanine aminotransferase, decreased sodium, increased potassium and increased aspartate aminotransferase, the FDA reported in its announcement of the approval.
In terms of Welireg’s side effects, Hilz said he experienced anemia and fatigue, but stated that drinking coffee has helped reduce the feeling of both side effects.
“I have a couple of cups of coffee, (I) don’t really feel the anemia much. … (and) a couple of cups of coffee to offset a little bit of fatigue,” Hilz explained. “But out of all the patients who probably shouldn’t have fatigue, no adrenal glands, classic anemia, you would think I would be affected more than most.”
The quality of life — an important factor for patients — was found to be most beneficial for patients receiving Welireg.
“(Patients) will likely find that (Welireg) is so much better-tolerated than any of the TKIs that they have been on before. And they don’t have to worry about the immune-related risks associated with immune checkpoint inhibitors,” Dr. James Brugarolas, founding director of the kidney cancer program at the Harold C. Simmons Comprehensive Cancer Center at UT Southwestern Medical Center, told CURE®. “So I think this is a drug that can bring quality of life … for patients, including patients (who) may not have other options because of their cardiovascular toxicity or autoimmune condition.”
After Hilz experienced in-person visits to receive Avastin every two weeks, three pills of Welireg before bed offered him “a very normal lifestyle.”
“I’m fully employed (as a) chief operating officer (and) I enjoy working. (Welireg) doesn’t really affect my work,” Hilz said. “The way I like to tell everybody is all I have to do to treat myself … is go to bed and take three pills.
“I mean, that is an amazing thing from a lifestyle perspective, right? You can go on trips, you can do whatever you want, you don’t have to worry about going in for an infusion every two weeks.”
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