Porphyria Testing & Counseling

Mary, living with acute hepatic porphyria


Alnylam Act®: Third-Party Genetic Testing and Counseling Programs Offered at No Charge

Alnylam is sponsoring no-charge third-party genetic testing and counseling for individuals who may carry a gene mutation known to be associated with acute hepatic porphyria (AHP). The Alnylam Act® program was created to reduce barriers to genetic testing and counseling to help people make more informed decisions about their health.


The genetic testing service is available in the United States and Canada and the genetic counseling service is available in the United States. Learn more about what genetic testing and counseling are and how the process works here or by downloading the brochures below. Healthcare professionals who use this program have no obligation to recommend, purchase, order, prescribe, promote, administer, use or support any Alnylam product.

About Acute Hepatic Porphyria

Acute hepatic porphyria (AHP) is comprised of four subtypes, each resulting from a genetic defect leading to deficiency in one of the enzymes of the heme biosynthesis pathway in the liver: acute intermittent porphyria (AIP), variegate porphyria (VP), hereditary coproporphyria (HCP), and ALAD-deficiency porphyria (ADP).

AHP refers to a family of rare, genetic diseases characterized by potentially life-threatening attacks and, for some patients, chronic debilitating symptoms that negatively impact daily functioning and quality of life.

Common symptoms include severe, diffuse abdominal pain, weakness, nausea, and fatigue.

HCP and VP are classified as acute but can also have symptoms that affect the skin—specifically blistering skin lesions on sun-exposed areas. Skin symptoms can be present with or without attacks.


HCPs: Want more information about AHP to share with your patients? Start Here


While Alnylam provides financial support for this program, all tests and services are performed by independent third parties. Healthcare professionals must confirm that the patients meet certain criteria to use the program. Alnylam receives de-identified patient data from this program, but at no time does Alnylam receive patient-identifiable information. Alnylam receives contact information for healthcare professionals who use this program.

Genetic testing and counseling may help to:
  • Identify risk of disease for patients and their family members
  • Shorten the time to diagnosis and prevent misdiagnoses
  • Help patients determine if they are eligible to participate in clinical trials
  • Provide information about support resources such as patient advocacy organizations


For testing and instructions, click here.
You can also download the Alnylam Act® Brochures for Acute Hepatic Porphyria below.

For Healthcare Professionals

Download PDF ›

For Patients

Download PDF ›


Interested in learning about our porphyria studies? Get started here.

Learn More ›


Porphyria is a family of rare, genetic diseases characterized by potentially life-threatening attacks and, for some patients, chronic debilitating symptoms.

Learn More ›


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