The FDA recently revved up its approval engine waving yet another specialty pharmacy checkered flag for Zokinvy (lonafarnib) from Eiger BioPharmaceuticals. Zokinvy is indicated for a rare genetic condition, Hutchinson-Gilford progeria syndrome, and for the treatment of certain processing-deficient progeroid laminopathies in patients one year of age and older. It is an oral formulation. Prior to this approval only supportive therapies were available for affected patients.
Progeria is caused by a point mutation in a single gene called lamin A. This mutated gene produces an abnormal form of the lamin A protein called progerin.
Progeria and Progeroid Laminopathies are serious, ultra-rare diseases characterized by premature and accelerated aging in children. Globally, there are an estimated 400 children with Progeria and another 400 children with Progeroid Laminopathies (in total, probably fewer than 200 in the US). Untreated, most patients will die from heart failure, heart attack or stroke. There is no known cure and the average life expectancy for the untreated children is around 14 years.
Zokinvy is dosed by height and weight, with an average dose of 175 milligrams per day; a bottle of 50-milligram and 75-milligram capsules will cost $21,500 and $32,000, respectively. That translates into an annual cost of $252,000 – $384,000.
Given the very small patient population and very high cost, it is almost assured that this therapy will be launched through exclusive distribution.
FDA Approves First Treatment for Hutchinson-Gilford Progeria Syndrome and Some Progeroid Laminopathies
SILVER SPRING, Md., Nov. 20, 2020 /PRNewswire/ — Today, the U.S. Food and Drug Administration approved Zokinvy (lonafarnib) capsules to reduce the risk of death due to Hutchinson-Gilford progeria syndrome and for the treatment of certain processing-deficient progeroid laminopathies in patients one year of age and older. Zokinvy is not approved for use in patients with other progeroid syndromes or laminopathies.
“Hutchinson-Gilford progeria syndrome and progeroid laminopathies are rare genetic diseases that cause premature aging and death and have a debilitating effect on people’s lives,” said Hylton V. Joffe, M.D., M.M.Sc, director of the Office of Rare Diseases, Pediatrics, Urologic and Reproductive Medicine in the FDA’s Center for Drug Evaluation and Research. “With today’s approval, Zokinvy is the first FDA-approved medication for these devastating diseases. The FDA will continue to work with stakeholders to advance the development of additional new, effective and safe therapies for these patients.”
Patients with Hutchinson-Gilford progeria syndrome and progeroid laminopathies experience accelerated cardiovascular disease from the buildup of defective progerin or progerin-like protein in cells. Before today’s approval, the only treatment options included supportive care and therapies directed towards the complications arising from the disease.
Zokinvy, a farnesyltransferase inhibitor, is an oral medication that helps prevent the buildup of defective progerin or progerin-like protein. The effectiveness of Zokinvy for the treatment of Hutchinson-Gilford progeria syndrome was demonstrated in 62 patients from two single-arm trials that were compared to matched, untreated patients from a separate natural history study. Compared to untreated patients, the lifespan of Hutchinson-Gilford progeria syndrome patients treated with Zokinvy increased by an average of three months through the first three years of treatment and by an average of 2.5 years through the maximum follow-up time of11 years. Zokinvy’s approval for the treatment of certain processing-deficient progeroid laminopathies that are very rare took into account similarities in the underlying genetic mechanism of disease and other available data.
The most common side effects included nausea vomiting, diarrhea, infection, decreased appetite and fatigue.
Zokinvy is contraindicated for co-administration with strong or moderate CYP3A inhibitors and inducers, as well as midazolam and certain cholesterol-lowering medications. Some patients treated with Zokinvy developed laboratory test abnormalities, such as changes in blood sodium and potassium levels, lowered white blood cell counts and increased liver blood tests. Routine blood laboratory testing should be obtained periodically. Eye toxicity was seen in animals so eye exams are recommended periodically and if there are new visual changes.
The FDA granted this application Priority Review designation. Zokinvy received Orphan Drug designation, which provides incentives to assist and encourage the development of drugs for rare diseases, and Breakthrough Therapy Designation. In addition, the manufacturer received a rare pediatric disease priority review voucher. The FDA’s rare pediatric disease priority review voucher program is intended to encourage development of new drugs and biologics to prevent and treat rare diseases in children. The FDA granted the approval of Zokinvy to Eiger BioPharmaceuticals, Inc.