The approval covers Rituxan Hycela’s use against relapsed or refractory follicular lymphoma and diffuse large B-cell lymphoma (DLBCL) in patients who have yet to receive treatment. It also covers chronic lymphocytic leukemia (CLL) patients, whether they have received a previous treatment or not.
Rituxan Hycela is a combination of Rituxan (rituximab) and Halozyme Therapeutics’ proprietary hyaluronidase human, an enzyme that helps deliver rituximab.
The new injected formulation includes the same tumor-inhibiting monoclonal antibody as intravenous Rituxan. Monoclonal antibodies are laboratory-produced molecules that strengthen the immune system’s attack on cancer cells.
Rituxan Hycela attaches to CD20, a protein found on certain types of immune-system B-cells. The injected formulation can be administered in five to seven minutes, which is much faster than the 90 minutes or more for intravenous Rituxan.
“With today’s approval of Rituxan Hycela, people with three of the most common blood cancers now have a new treatment option which provides efficacy comparable with intravenous Rituxan and can be delivered under the skin in minutes instead of hours through IV infusion,” Dr. Sandra Horning, Genentech’s chief medical officer, said in a press release. “People who benefit from Rituxan may receive years of repeated treatments for their blood cancer, so an option that reduces the administration time can be important.”
U.S. regulators based their approval on the results of four clinical trials that enrolled nearly 2,000 people. Three of the trials were Phase 3 and one a Phase 1b.
The Phase 3 SABRINA trial (NCT01200758) combined Rituxan Hycela with chemotherapy in previously untreated follicular lymphoma patients. The Phase 3 MabEase trial (NCT01649856) assessed the drug in previously untreated DLBCL patients. The Phase 1b trial, SAWYER (NCT01292603), evaluated Rituxan Hycela in previously untreated CLL.
The Phase 3 PreMab trial was a patient preference study (NCT01724021). Its objective was to see whether patients with previously untreated follicular lymphoma or DLBCL preferred injected Rituxan Hycela or intravenous rituximab.
Together, the studies demonstrated that injected Rituxan Hycela was as effective as the IV version of rituximab. The PreMab study showed that 77 percent of patients preferred Rituxan Hycela over intravenous Rituxan, mostly because Rituxan Hycela’s administration required less time.
A drawback of Rituxan Hycela is that patients must receive at least one dose of intravenous Rituxan before receiving the injected formulation.
Adverse reactions were comparable between Rituxan Hycela and Rituxan, the trials showed. In follicular lymphoma, the most common reactions were infections and low white blood cell count. In DLBCL, the most common reactions were infections, low white and red blood cell counts, and hair loss. The most common reactions in CCL were infections, low white cell count, and low platelet count.
Rituxan Hycela is expected to reach the U.S. market in a week or two. Rituxan will continue to be sold as an IV formulation.