Claseprubart (DNTH103) is an inhibitor targeting C1s of the complement system and an inhibitor of the C1 component of the complement cascade. Claseprubart is in phase 2 clinical evaluation. Claseprubart has application potential in research related to multifocal motor neuropathy and generalized myasthenia gravis [1] [2] [3].
In Vitro, Co-incubation of DNTH103 (0.1 μM, 1 μM) with complement-containing serum from AChR-positive myasthenia gravis patients significantly reduces the muscle contraction fatigue index and improves neuromuscular transmission function in a human iPSC-derived motor neuron-muscle cell co-culture myasthenia gravis model. Its efficacy is superior to that of anti-C5 antibody at the same concentration, and it exerts no significant effect on serum samples from healthy individuals[3].
References:
[1]. Gokhale S, et al. Classical Pathway Inhibition with Anti-active C1s Antibody DNTH103 Prevents Neurotransmission Impairment in a Preclinical Model of Myasthenia Gravis (S15. 001)[C]//Neurology. Hagerstown, MD: Lippincott Williams & Wilkins, 2024, 102(7_supplement_1): 5614.
[2]. Katzberg H, et al. Prospects for multi-focal motor neuropathy treatment by complement inhibition[J]. Expert Opinion on Investigational Drugs, 2025, 34(6): 453-457.
[3]. Ho AWS, et al. Long lasting complement neutralisation by RAY121, an engineered anti-C1s antibody with C1q displacement function. EBioMedicine. 2025;122:106009.
In Vitro, Co-incubation of DNTH103 (0.1 μM, 1 μM) with complement-containing serum from AChR-positive myasthenia gravis patients significantly reduces the muscle contraction fatigue index and improves neuromuscular transmission function in a human iPSC-derived motor neuron-muscle cell co-culture myasthenia gravis model. Its efficacy is superior to that of anti-C5 antibody at the same concentration, and it exerts no significant effect on serum samples from healthy individuals[3].
References:
[1]. Gokhale S, et al. Classical Pathway Inhibition with Anti-active C1s Antibody DNTH103 Prevents Neurotransmission Impairment in a Preclinical Model of Myasthenia Gravis (S15. 001)[C]//Neurology. Hagerstown, MD: Lippincott Williams & Wilkins, 2024, 102(7_supplement_1): 5614.
[2]. Katzberg H, et al. Prospects for multi-focal motor neuropathy treatment by complement inhibition[J]. Expert Opinion on Investigational Drugs, 2025, 34(6): 453-457.
[3]. Ho AWS, et al. Long lasting complement neutralisation by RAY121, an engineered anti-C1s antibody with C1q displacement function. EBioMedicine. 2025;122:106009.
















