Report on New Patented Drugs - Agenerase

Under its transparency initiative, the PMPRB publishes the results of the reviews of new patented drugs by Board Staff, for purposes of applying the PMPRB's Excessive Price Guidelines (Guidelines), for all new active substances introduced after January 1, 2002.

Brand Name: Agenerase

Generic Name: (amprenavir)

DIN:

DIN 02243541 50 mg capsule DIN 02243542 150 mg capsule DIN 02243543 15 mg/mL oral solution

Patentee: GlaxoSmithKline Inc.

Indication - as per product monograph:

For the treatment of protease inhibitor experienced, HIV-1 infected patients, in combination with other antiretroviral agents. In protease-inhibitor naïve patients, amprenavir is less effective than indinavir. In heavily pretreated protease-inhibitor experienced patients, amprenavir has not been sufficiently studied.

Notice of Compliance: March 1, 2001

Date of First Sale: March 16, 2001

Date of Issuance of First Patent(s) Pertaining to the Medicine: January 7, 2003

ATC Class: J05AE05 Antivirals for systemic use, Direct acting antivirals, Protease inhibitors.

Application of the Guidelines

Summary

The introductory prices of Agenerase at the date of first sale were found to be within the Guidelines because the cost of therapy did not exceed the cost of therapy of existing drugs in the therapeutic class comparison and the prices did not exceed the range of prices in other comparator countries where Agenerase is sold or did not do so by an amount sufficient to trigger any of the investigation criteria under the Compliance and Enforcement Policy.

Scientific Review

Agenerase is a new active substance and the PMPRB's Human Drug Advisory Panel (HDAP) recommended that Agenerase be reviewed as a category 3 new medicine (provides moderate, little or no therapeutic advantage over comparable medicines).

The Therapeutic Class Comparison (TCC) test of the Guidelines provides that the price of a category 3 new drug product cannot exceed the prices of other drugs that treat the same disease or condition. Comparators are generally selected from among existing drug products in the same 4th level of the Anatomical Therapeutic Chemical (ATC) System that are clinically equivalent in addressing the approved indication. See the PMPRB's Compendium of Guidelines, Policies and Procedures for a more complete description of the Guidelines and the policies on TCCs.

The HDAP recommended protease inhibitors Crixivan (indivavir), Fortovase (saquinavir), Viracept (nelfinavir) and Kaletra (lopinavir/ritonavir) as the most appropriate comparators to Agenerase 150 mg capsule and Kaletra for Agenerase 15 mg/mL. These agents share the same 4th level ATC classification and indication as Agenerase. The HDAP recommended ritonavir boosting for Agenerase and the protease inhibitor comparators, Crixivan (indivavir) and Fortovase (saquinavir). This is consistent with the Guidelines of the U.S. Department of Health and Human Services. The HDAP did not identify any comparators for Agenerase 50 mg capsule and recommended that it would be appropriate to compare it to Agenerase 150 mg capsule on a milligram-to-milligram basis.

The Guidelines provide that the dosage recommended for comparison purposes will normally not be higher than the maximum of the usual recommended dosage. The recommended comparable dosage regimens for Agenerase and the comparators are based on their respective product monographs and supported by clinical literature.

Price Review

Under the Guidelines, the introductory price of a new category 3 drug product will be presumed to be excessive if it exceeds the price of all of the comparable drug products in the TCC test, or if it exceeds the prices of the same medicine in the seven countries listed in the Patented Medicines Regulations. As shown in the table below, the prices of Agenerase (150 mg capsules and 15 mg/mL) were within the Guidelines in the introductory period (March 16 to June 30, 2001) as the cost of therapy did not exceed the cost of therapy with the comparator medicines or did not do so by an amount which would trigger the investigation criteria.

1 Publicly available price as per the Patented Medicines Regulations 2 Liste de médicaments, Régie de l'assurance maladie du Québec, Avril 2001 3 Liste de médicaments, Régie de l'assurance maladie du Québec, Octobre 2001

As no comparators were identified for the 50 mg capsule, the price of the 50 mg capsule was compared to the price of the 150 mg capsule in a Reasonable Relationship test. Its price was within the Guidelines at introduction.

At the date of first sale, all three strengths of Agenerase were also being sold in France, Germany, Italy, Switzerland, United Kingdom and the United States. In compliance with the Guidelines, the price in Canada did not exceed the range of prices in those countries; the price of Agenerase in Canada was the third highest, above the median for the 50 mg capsule, second highest, above the median for the 150 mg capsule and third highest above the median, for the 15 mg/mL solution.

Where comparators and dosage regimens are referred to in the Summary Reports, they have been selected by the PMPRB Staff and the HDAP for the purpose of carrying out the PMPRB's regulatory mandate, which is to review the prices of patented medicines sold in Canada to ensure that such prices are not excessive. The publication of these reports is also part of the PMPRB's commitment to make its price review process more transparent.

The information contained in the PMPRB's Summary Reports should not be relied upon for any purpose other than its stated purpose and is not to be interpreted as an endorsement, recommendation or approval of any drug nor is it intended to be relied upon as a substitute for seeking appropriate advice from a qualified health care practitioner.

References

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