Caspofungin

Caspofungin is an inhibitor of β-1,3-glucan synthase with IC50 value of 0.6 nmol/L in membrane preparations of C. albicans [1, 2]. 

β-1,3-glucan synthase plays a critical role in biosynthesis of β-(1,3)-D-glucan, an essential cell wall component of many pathogenic fungi that is absent in the mammalian host. Inhibition of β-1,3-glucan synthase provides a potential therapeutic option for treating serious and life-threatening fungal infections [1]. 

Caspofungin exhibited inhibitory effect against 400 bloodstream Candida species with MIC90 value of 0.25 μg/mL. Moreover, all azole-resistant isolates were susceptible to Caspofungin at concentrations of ≤ 0.5 μg/mL. In addition, Caspofungin showed a postantifungal effect against C. albicans, which lasted for 6 ~ 8 h, at concentrations of 0.125 ~ 1 μg/mL [2]. 

In 140 patients with mucosal candidiasis, 63% of whom had esophageal involvement and 98% of whom had acquired immunodeficiency syndrome (AIDS), the response rates among the Caspofungin recipients (35, 50, or 70 mg, i.v., q.d., for 7 ~ 14 d) with exclusively oropharyngeal infections was 84% ~ 93%, higher than 67% among those assigned to receive Amphotericin B (0.5 mg/kg, i.v., q.d., for 7 ~ 14 d) [2]. 

References:

[1]. Leonard W R Jr, Belyk K M, Conlon D A, et al. Synthesis of the antifungal beta-1,3-glucan synthase inhibitor CANCIDAS (caspofungin acetate) from pneumocandin B0. The Journal of Organic Chemistry, 2007, 72(7): 2335-2343.

[2]. Deresinski S C, Stevens D A. Caspofungin. Clinical Infectious Diseases, 2003, 36(11): 1445-1457.