By Kirell Lakhman

The largest pharmacy in the US next month will launch a pharmacogeneic-testing program that will effectively shut out scores of clinical labs but enable a few to participate in its new Best Test Genetics Network PPO.

But the program, which will be run through the genetics benefits management company Generation Health, could also save the Caremark money and potentially improve outcomes.

CVS Caremark said it will begin providing the service for 13 approved drugs initially as part of the pilot program.

The drugs include the immunosuppressant azathioprine; the breast cancer hormone therapy tamoxifen; the acute nonlymphocytic leukemia drug thioguanine; the seizure disorder drug carbamezepine; the HIV drug abacavir; and anticoagulant clopidogrel (Sanofi-Aventis/Bristol-Myers Squibb's brand, Plavix, is set to go off patent soon).

Seven branded drugs dispensed through Caremark's specialty pharmacy business will also be tested, including hepatitis C treatments Pegasys and Copegus; chronic myeloid leukemia drugs Gleevec, Tasigna, and Sprycel; non-small cell lung cancer drug Tarceva; and the EGFR/HER2 dual inhibitor breast-cancer treatment Tykerb.

The company chose the 13 drugs after identifying “well-validated molecular tests that identify genetic variants which have the ability to predict drug response linked to meaningful clinical outcomes and that is actionable in the outpatient setting."

The move could affect the entire clinical lab industry due to the sheer breadth of Caremark's play in the health-care industry: It operates more than 7,000 CVS/pharmacy and Longs Drugs stores, and its Caremark Pharmacy Services pharmacy benefit-management division provides services to more than 2,000 health plans.

Under Caremark's pilot program, around 150,000 eligible members will have the option to sign up for the PGx-testing service beginning in July. The company said it plans to add clients representing up to 1 million lives over the ensuing few months.

Caremark's announcement follows a promise made in May by rival Medco to expand its pharmacogenetic test offerings to all of its clients beginning in July.

The companies' offerings are similar, but Caremark's differs in one way: It will not offer genetic testing to gauge warfarin metabolism.

In a statement last week, Caremark said its testing service "will be coordinated through the industry’s first Best Test Genetics Network, a preferred provider organization of high-quality diagnostic service providers that offer evidence-based genetic and molecular testing."

Caremark was able to create the service after buying a majority stake in the genetics benefits management company Generation Health late last year. Generation Health CEO Rick Schatzberg last week told my colleague Turna Ray that Caremark has created the Best Test Genetics Network in response to the variation in pricing and quality among clinical labs today.

“As you know, many labs offer the same or similar tests,” Schatzberg said. “What we have seen, however, is that in addition to there being substantial pricing variation among labs, there is also significant variation in experience, testing turn-around time, technology used to conduct tests, the use of proficiency testing (internal and external), and the quality of their result reports. Lab and test-level credentialing ensure that the labs that support our programs meet the highest standards in each of these areas."

In its statement last week, Caremark said it is launching the Best Test Genetics Network to “manage the rapid growth of testing costs for payors," adding that "[t]here is a growing desire by clients to tailor pharmaceutical treatment based on genetic inheritance and our new program helps save payors and patients time and money while improving health outcomes."

It wasn't immediately clear whether Caremark has chosen the labs for its PPO, or what the inclusion criteria are.

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