Increased risk of marked hepatic enzyme elevations in patients taking SOMAVERT (pegvisomant) in combination with a somatostatin analogue - For the Public

Help on accessing alternative formats, such as Portable Document Format (PDF), Microsoft Word and PowerPoint (PPT) files, can be obtained in the alternate format help section.

Contact: Marketed Health Products Directorate (MHPD) Enquiries

The Health Products and Food Branch (HPFB) posts on the Health Canada web site safety alerts, public health advisories, press releases and other notices as a service to health professionals, consumers, and other interested parties. These advisories may be prepared with Directorates in the HPFB which includes pre-market and post-market areas as well as market authorization holders and other stakeholders. Although the HPFB grants market authorizations or licenses for therapeutic products, we do not endorse either the product or the company. Any questions regarding product information should be discussed with your health professional.

This is duplicated text of a letter from Pfizer Canada Inc.
Contact the company for a copy of any references, attachments or enclosures.

Public Communication
Health Canada Endorsed Important Safety Information on SOMAVERT (pegvisomant)

June 2, 2008

Subject: Risk of liver problems with the use of SOMAVERT^® (pegvisomant) in combination with a somatostatin analogue for the treatment of acromegaly

Pfizer Canada Inc., following discussions with Health Canada, is informing you of the increased risk of liver problems when SOMAVERT (pegvisomant) is taken in combination with a somatostatin analogue (octreotide acetate).

SOMAVERT is a medicine used for the treatment of acromegaly (a disease caused when the body produces too much growth hormone). SOMAVERT blocks the effect of excess growth hormone and improves the symptoms of acromegaly. Octreotide acetate is another type of medicine from a group of drugs called somatostatin analogues, which are also used to treat acromegaly.

Pfizer Canada is sending a letter to health professionals providing them with safety information from a post-marketing clinical study which looked at SOMAVERT use in combination with octreotide acetate. In this study, 3 out of 26 patients who were taking these medications together had much higher than normal liver function test results. Two of these patients received higher doses than usually recommended of octreotide acetate (30 mg every 2 weeks) combined with a normal dose of SOMAVERT (10 mg daily). All three patients completely recovered once both drugs were stopped. Studies published in medical journals found similar results using normal doses of somatostatin analogues.

According to standard practice and the existing product information, physicians should request that blood tests be done before starting treatment with SOMAVERT and regularly during the course of treatment to check how patients are responding to their medicine, to change the dose if necessary and to check for liver problems.

Patients should contact their doctor immediately if they notice any of the following:

• Sudden yellowing of the skin or whites of the eyes, or darkening of the urine
• Unexplained fatigue, nausea, vomiting, loss of appetite or pain in the stomach area

As part of Pfizer post-marketing safety activities for SOMAVERT, reports of abnormal liver tests will continue to be closely followed and you will be informed of new information as it becomes available.

A copy of the healthcare professional letter and this communication are available on the Health Canada website. This letter can also be viewed on the Canadian website of  Pfizer Canada Inc.

Patients who have additional questions may contact Pfizer Canada's medical information line at 1-800-463-6001.

For media inquiries, please contact Ms. Julie-Catherine Racine, Pfizer Canada Inc., 514-693-4602.

Managing marketed health product-related adverse reactions depends on health care professionals and consumers reporting them. Reporting rates determined on the basis of spontaneously reported post-marketing adverse reactions are generally presumed to underestimate the risks associated with health product treatments. Any case of serious liver dysfunction or other serious or unexpected adverse reactions in patients receiving SOMAVERT should be reported to Pfizer Canada Inc. or Health Canada at the following addresses:

Sincerely,

original signed by

Bernard Prigent, MD, MBA
Vice-President and Medical Director
Pfizer Canada Inc.