In US: For Research Use Only. Not for Use in Diagnostic Procedures. HEMOCLOT™ LA-S is a simplified dRVV reagent to screen for the presence of Lupus Anticoagulants. Diluted Russell’s Viper Venom Test (dRVVT) are simplified reagents for the specific detection of lupus anticoagulant (LA), using a manual, semi-automated or automated clotting method.