Cabaletta cleared to launch Phase 1/2 trial of cell therapy for gMG
CABA-201 to be tested in patients with, without antibodies targeting AChR
The U.S. Food and Drug Administration (FDA) has given Cabaletta Bio the go-ahead to launch a Phase 1/2 clinical trial testing its cell therapy CABA-201 in people with generalized myasthenia gravis (gMG).
The upcoming trial is expected to enroll a dozen adults with gMG — six who are positive for antibodies targeting the acetylcholine receptor (AChR), the most common type of MG-driving antibody, and another six who are negative for these antibodies.
All participants will be treated with CABA-201 at a dose of 1 million cells per kilogram of body weight. This dose also is being used in other ongoing trials that are testing the therapy for disorders such as lupus and myositis, a group of rare conditions that can cause muscles to become weak and painful.
“Consistent with previously announced CABA-201 trials, the Phase 1/2 clinical trial design for CABA-201 in gMG includes the same starting dose as used in the previously cleared clinical trials with CABA-201 and parallel cohorts [groups] of six patients,” Steven Nichtberger, MD, CEO and co-founder of Cabaletta, said in a company press release.
“While we remain on track to deliver initial clinical data from CABA-201 treated patients with lupus and/or myositis in the first half of 2024, we are continuing to expand our CABA-201 portfolio beyond rheumatology and into neurology,” Nichtberger said.
Therapy candidate will be 2nd from Cabaletta in trial for generalized MG
Myasthenia gravis is driven by self-reactive antibodies that interfere with the communication between nerves and muscle cells, causing patients to experience muscle weakness and other symptoms. Antibodies are immune proteins made by B-cells, a specialized type of immune cell.
CABA-201 is a one-time CAR T-cell therapy that’s designed to deplete B-cells. The therapy works by first collecting a patient’s T-cells, which are another type of immune cell.
These T-cells are then engineered in a laboratory to be equipped with a chimeric antigen receptor or CAR, which is a cellular receptor designed to prime T-cells to attack a specific target. For CABA-201, T-cells are equipped with a CAR that’s specific to CD19, a protein that’s found on the surface of B-cells.
The engineered cells are then transferred back into the patient, with the aim of temporarily, but strongly, eliminating B-cells to control disease.
The new Phase 1/2 trial will be testing whether the therapy appears to work as intended in gMG patients.
Cabaletta did not provide details on where the upcoming trial will be conducted. But the inclusion criteria will be based on age — open to patients ages 18 and 70 — having a diagnosis of gMG, and experiencing disease activity despite standard of care therapies.
“Our clinical operations team is well positioned to execute the gMG program based on experience with MG sites,” Nichtberger said.
The company also is developing another CAR T-cell therapy called MuSK-CAART, which is specifically designed to treat people with MG who are positive for antibodies targeting a protein called muscle-specific tyrosine kinase, or MuSK. The company is testing the therapy in a Phase 1 clinical trial (NCT05451212), which is recruiting participants at several sites in the U.S.