December 2, 2019Regulatory
Acute hepatic porphyria (AHP) refers to a family of rare genetic diseases characterized by potentially life-threatening attacks and, for some people, chronic debilitating symptoms that negatively impact daily functioning and quality of life. In AHP, there is a buildup of toxic porphyrin molecules which are formed during the production of heme (which helps bind oxygen in the blood). The symptoms of AHP often resemble those of other diseases in the gastrointestinal, gynecological, and neurological or neuropsychiatric areas. Severe symptoms can lead to hospitalizations and unnecessary procedures. Misdiagnosis is common, and people with AHP can wait years for a confirmed diagnosis.
There are four types of AHP:
1. Acute intermittent porphyria (AIP)
2. Variegate porphyria (VP)
3. Hereditary coproporphyria (HCP)
4. ALAD-deficiency porphyria (ADP)
The FDA has granted approval to Givlaari (givosiran) for the treatment of adult patients with AHP. The approval of Givlaari was based on the results of a clinical trial of 94 patients with AHP. Patients received a placebo or Givlaari. Givlaari's performance was measured by the rate of porphyria attacks that required hospitalizations, urgent health care visits or intravenous infusion of hemin at home. Patients who received Givlaari experienced 70% fewer porphyria attacks compared to patients receiving a placebo. Common side effects for patients taking Givlaari were nausea and injection site reactions. Health care professionals are advised to monitor patients for anaphylactic (allergic) reaction and renal (kidney) function. Patients should have their liver function tested before and periodically during treatment.
The FDA granted this application Breakthrough Therapy designation and Priority Review designation. Givlaari also received Orphan Drug designation, which provides incentives to assist and encourage the development of drugs for rare diseases. The FDA granted the approval of Givlaari to Alnylam Pharmaceuticals.