FDA approved Myfortic (mycophenolic acid) for Kidney Transplant Rejection ProphylaxisFDA approved new kidney transplant drug Myfortic to prevent organ rejection

Myfortic is an antimetabolite immunosuppressant. The label does not provide detailed mechanism of action; however, as mycophenolic acid, it inhibits inosine monophosphate dehydrogenase, thereby blocking de novo purine synthesis and suppressing lymphocyte proliferation. (Not explicitly stated in label; inferred from drug class.)

Myfortic is indicated for prophylaxis of organ rejection in adult patients receiving a kidney transplant and in pediatric patients 5 years of age and older who are at least 6 months post kidney transplant. It is to be used in combination with cyclosporine and corticosteroids. Limitations: Myfortic delayed-release tablets and mycophenolate mofetil (MMF) tablets and capsules should not be used interchangeably without physician supervision because the rate of absorption is not equivalent.

Adults: 720 mg by mouth twice daily (1,440 mg total daily dose) on an empty stomach, 1 hour before or 2 hours after food intake. Pediatric patients 5 years and older (at least 6 months post-transplant): 400 mg/m² body surface area (BSA) twice daily, up to a maximum of 720 mg twice daily. Tablets should be swallowed whole; do not crush, chew, or cut. Pediatric patients with BSA 1.19 to 1.58 m² may be dosed with three 180 mg tablets or one 180 mg plus one 360 mg tablet twice daily (1,080 mg daily dose). Patients with BSA >1.58 m² may be dosed with four 180 mg tablets or two 360 mg tablets twice daily (1,440 mg daily dose). Doses for BSA <1.19 m² cannot be accurately administered with available formulations.

Two randomized, active-controlled, double-blind trials were conducted. In the de novo trial, patients received Myfortic 1.44 g/day (N=213) or MMF 2 g/day (N=210) within 48 hours post-transplant for 12 months, with cyclosporine and corticosteroids; 41% received antibody induction. In the conversion trial, stable patients at least 6 months post-transplant on MMF 2 g/day were randomized to Myfortic 1.44 g/day (N=159) or MMF 2 g/day (N=163) for 12 months. The most common adverse reactions (≥20%) in the Myfortic arm were anemia, leukopenia, constipation, nausea, diarrhea, vomiting, dyspepsia, urinary tract infection, CMV infection, insomnia, and postoperative pain. Discontinuation due to adverse reactions was 18% in the Myfortic arm vs 17% in the MMF arm in the de novo trial. The trials were not designed to support comparative claims for adverse reactions.

Specific warnings and contraindications are not detailed in the provided label text. Clinicians should refer to the full prescribing information for comprehensive safety data.

Myfortic provides an alternative to mycophenolate mofetil for prophylaxis of kidney transplant rejection when used with cyclosporine and corticosteroids. It is not interchangeable with MMF without supervision. The delayed-release formulation may offer different absorption characteristics, but comparative efficacy and safety were similar in trials.