Clinical Trial: Treating HCL Without Chemo while Limiting Toxicities
Vemurafenib is a non-chemotherapy treatment for melanoma and has shown promising results in classic hairy cell leukemia. Like all drugs, it has side effects. Researchers at the Scripps Clinic in La Jolla are studying the combination of vemurafenib and rituximab in HCL patients. In their trial, they are using a low dose of vemurafenib to limit toxicities for patients. In May, Dr. David Hermel of the Scripps Clinic spoke about their trial during a webinar hosted by the Hairy Cell Leukemia Foundation.
Background
The Scripps clinical trial was developed in part due to the risks of chemotherapy. Patients treated with Cladribine can experience prolonged immunosuppression, which doctors and researchers were particularly concerned about during the COVID-19 pandemic.
In 2015, investigators, including Sascha Dietrich from the University of Heidelberg, published positive results for patients who received low-dose Vemurafenib. The investigators concluded that further research on Vemurafenib dosing regimens for HCL patients was necessary. Read the 2015 study. >>
A later clinical trial conducted in the United States and Italy used Vemurafenib at 960 milligrams, administered twice daily for eight weeks. Additionally, the trial included eight doses of Rituximab administered every other week.
Read published results from this clinical trial. >>
Initial Trial Data is Promising
The 2015 study and trial conducted in the US and Italy empowered Scripps investigators to develop a protocol using low-dose Vemurafenib and Rituximab to create a standard treatment regimen with fewer side effects for vulnerable patients. Instead of the standard dose of 960 milligrams twice daily, the Scripps trial is using a lower dose of 240 milligrams twice daily. During the eight-week trial, patients take Vemurafenib twice daily and receive eight intravenous infusions of Rituximab every two weeks.
In December 2023, Scripps investigators presented initial data from their clinical trial. The early data showed positive results, with all patients experiencing hematologic recovery and complete responses. The relapse-free survival rate was 100% during the short follow-up period, and no serious adverse events were reported.
You can read Scripps' conference abstract for more details.
Treatment Options are Growing
Targeted therapies, such as BRAF inhibitors, have significantly advanced cancer treatment by offering personalized and more effective treatment options for patients with specific genetic mutations. By understanding the molecular mechanisms driving cancer growth, researchers can develop therapies that target these pathways, leading to improved patient outcomes and quality of life. Vemurafenib plus rituximab is a non-chemotherapy approach that may continue to revolutionize the treatment landscape for HCL patients.
Links
Materials (slides and transcript) from Dr. David Hermel’s May 23rd webinar