Rigel Sues Hetero Labs to Block Annora Unit’s Copy of Tavalisse

Rigel Pharmaceuticals Inc. alleges that a generic version of Tavalisse proposed by Hetero Labs Ltd.’s Annora Pharma Private Ltd. infringes five patents for the drug, used to treat a chronic immune disease that leads to excessive bleeding, according to a federal lawsuit in New Jersey.

People with immune thrombocytopenia, or ITP, have unusually low levels of platelets, the cells that help blood clot, leading to easy or excessive bruising or bleeding.

Tavalisse is a fostamatinib disodium tablet used for the treatment of thrombocytopenia in adult patients with chronic ITP who have had an insufficient response to a previous ...