Letolizumab

Letolizumab (BMS-986004) is a monoclonal antibody targeting CD40L, which is produced to express mutant IgG1 lacking effector function, including Fc binding and complement fixation. Letolizumab reduces rejection, thromboembolism and prolongs the survival time.

Letolizumab inhibits the viability of CD40L trimer and CHO-CD40L in human B cell (IC₅₀ values of 3.6 nM and 1.3 nM, respectively) or nonhuman primate B cell (IC₅₀ values of 3.8 nM and 7.3 nM, respectively)^[2].
Letolizumab (2, 10 and 20 mg/kg; i.v.; once a week for 10 weeks) prolongs the survival time of rhesus macaques after renal transplantation^[2].

References:
[1]. Karnell JL, et al. Targeting the CD40-CD40L pathway in autoimmune diseases: Humoral immunity and beyond. Adv Drug Deliv Rev. 2019 Feb 15;141:92-103.
[2]. Kim SC, et al. Fc-Silent Anti-CD154 Domain Antibody Effectively Prevents Nonhuman Primate Renal Allograft Rejection. Am J Transplant. 2017 May;17(5):1182-1192.
[3]. Spicer P, et al. Costimulatory pathway targets for autoimmune and inflammatory conditions: clinical successes, failures, and hope for the future. Expert Opin Investig Drugs. 2019 Feb;28(2):99-106.