Anchen Pharmaceuticals, Inc., the operating subsidiary of Par Pharmaceutical Companies, has received final approval from the US Food and Drug Administration (FDA) for its Abbreviated New Drug Application for tretinoin capsules, 10 mg. Tretinoin capsules is the generic version of Vesanoid capsules and is used in the treatment of acute promyelocytic leukaemia.

Par expects to begin shipping the product before the end of the month. According to IMS Health data, annual US sales of tretinoin are approximately $29 million.

Tretinoin Capsules are indicated for the induction of remission in patients with acute promyelocytic leukemia (APL), French-American-British (FAB) classification M3 (including the M3 variant), characterised by the presence of the t(15;17) translocation and/or the presence of the PML/RARa gene who are refractory to, or who have relapsed from, anthracycline chemotherapy, or for whom anthracycline based chemotherapy is contraindicated. Tretinoin is for the induction of remission only. The optimal consolidation or maintenance regimens have not been defined, but all patients should receive an accepted form of remission consolidation and/or maintenance therapy for APL after completion of induction therapy with tretinoin.

Tretinoin is contraindicated in patients with a known hypersensitivity to tretinoin, any of its components, or other retinoids.

Patients with acute promyelocytic leukaemia (APL) are at high risk in general and can have severe adverse reactions to tretinoin. About 25 per cent of patients with APL treated with tretinoin have experienced a syndrome called the retinoic-acid-APL (RA-APL) syndrome characterized by fever, dyspnea, acute respiratory distress, weight gain, radiographic pulmonary infiltrates, pleural and pericardial effusions, edema, and hepatic, renal, and multi-organ failure.  During tretinoin treatment about 40 per cent of patients will develop rapidly evolving leukocytosis. Patients who present with high WBC at diagnosis (5x109/L) have an increased risk of a further rapid increase in WBC counts.  Rapidly evolving leukocytosis is associated with a higher risk of life threatening complications. There is also a high risk that a severely deformed infant will result if tretinoin is administered during pregnancy.

Par Pharmaceutical Companies, Inc. is a privately held, specialty pharmaceutical company. It develops, manufactures and markets high barrier-to-entry generic drugs and niche, innovative proprietary pharmaceuticals.