APS Foundation of America

Yes, natural benzimidazoles exist. The core scaffold appears in vitamin B12 (cobalamin), where 5,6-dimethylbenzimidazole coordinates cobalt as its axial ligand—essential for DNA synthesis and red blood cell formation. This was key to benzimidazole's discovery in the 1940s–50s during B12 research. Unlike ivermectin (derived from microbial avermectins), the antiparasitic drugs fenbendazole/mebendazole are fully synthetic benzimidazole analogs designed to mimic nucleotide-like structures for microtubule disruption in parasites. No direct natural sources produce these specific veterinary/human versions. Sources: Nobel-related B12 studies; IntechOpen review on benzimidazole (2019); Wikipedia/PMC refs on vitamin B12 structure.

Optimal vitamin D (>30 ng/ml) may benefit aPL-positive pregnancies by inhibiting aPL-induced tissue factor (reducing thrombosis), suppressing NET formation/cytotoxicity on endothelium & placenta, & boosting regulatory T cells for immune tolerance. Low levels (<30 ng/ml) are common in APS/OAPS (32-62% deficient/insufficient per meta-analyses), correlate with higher thrombosis (63% in deficient), RPL, preeclampsia, & aPL positivity in RPL cohorts. In vitro & observational data link deficiency to worse placental outcomes; supplementation endorsed as adjunct in deficient cases by APS congress. Low VD appears a modifiable risk factor.