Investigating an mRNA CAR T-cell Therapy, Known as Descartes-08, as a Potential Approach to Treat Myasthenia Gravis

Cannot have received: systemic treatment for gMG other than acetylcholine esterase inhibitors

No history of systemic treatment for gMG other than acetylcholine esterase inhibitors

Cannot have received: intravenous immunoglobulin (IVIG)

Treatment with intravenous immunoglobulin (IVIG) or plasma exchange within 4 weeks prior to the Baseline visit

Cannot have received: plasma exchange

Treatment with intravenous immunoglobulin (IVIG) or plasma exchange within 4 weeks prior to the Baseline visit

Cannot have received: anti-CD20 antibody (rituximab, ocrelizumab)

Treatment with rituximab or ocrelizumab within 12 months prior to Baseline visit

Cannot have received: calcineurin inhibitor (tacrolimus, cyclosporine, cyclophosphamide)

treatment with calcineurin inhibitors (e.g. tacrolimus, cyclosporine, cyclophosphamide), Neonatal Fc receptor antagonists, and/or other biologics within 3 weeks prior to planned leukapheresis and within 8 weeks prior to Baseline visit

Cannot have received: Neonatal Fc receptor antagonist

treatment with calcineurin inhibitors (e.g. tacrolimus, cyclosporine, cyclophosphamide), Neonatal Fc receptor antagonists, and/or other biologics within 3 weeks prior to planned leukapheresis and within 8 weeks prior to Baseline visit

Cannot have received: biologic therapy

treatment with calcineurin inhibitors (e.g. tacrolimus, cyclosporine, cyclophosphamide), Neonatal Fc receptor antagonists, and/or other biologics within 3 weeks prior to planned leukapheresis and within 8 weeks prior to Baseline visit

Cannot have received: C5a inhibitor (eculizumab)

Exception: patients who have been receiving a C5a inhibitor for more than 8 weeks and meet other criteria for enrollment are eligible

The patient has started treatment with a complement 5a (C5a) inhibitor, such as eculizumab, within 8 weeks of Baseline visit. (NOTE: patients who have been receiving a C5a inhibitor for more than 8 weeks and meet other criteria for enrollment are eligible for treatment).

Cannot have received: BCMA-directed therapy

Prior treatment with B-cell maturation antigen (BCMA)-directed therapy (e.g. monoclonal antibody, T-cell engager, or chimeric antigen receptor T-cell [CAR-T])

Cannot have received: investigational agent

Treatment with any investigational agent 4 weeks prior to screening or 5 half-lives of the investigational drug (whichever is longer)

Cannot have received: live vaccine

Exception: mRNA-based vaccines and Janssen Covid-19 vaccine are not considered live

Receipt of a live vaccination within 4 weeks prior to Baseline visit or intent to receive live vaccination during the study (Note: messenger RNA [mRNA]-based vaccines such as those against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are not considered live; likewise, the Janssen Covid-19 vaccine is not live).