But the drug has become a poster child for high drug costs in the U.S, running about $84,000 for 12 weeks of treatment, which has led to criticism from payers and lawmakers. Its high cure rate has been driving demand among physicians and patients.
However, Sovaldi's newest competition is from another Gilead drug, Harvoni, which received FDA approval this month. It's the first single tablet regimen for hepatitis C patients, it does not require the use of interferon, and it has a slightly higher cure rate. It also has an even higher price tag, costing about $94,500 for a 12-week course of treatment.
Gilead executives told investors that lower sales in the third quarter, as compared with the second quarter of the year, may be due to some doctors choosing to wait for Harvoni before starting patients on treatment. Gilead reported $3.5 billion in sales of Sovaldi in the second quarter.
Executives at the company also noted that insurers may have been unprepared for the Sovaldi prescriptions that flooded in this year but they are likely now to place stricter policies around Harvoni, which may lead to slower adoption of the drug.
Sales of Truvada, a Gilead drug approved in 2012 that reduces the risk of sexually acquiring HIV, rose 8% to $875.4 million in the third quarter of 2014 compared with the third quarter of 2013.
Gilead updated its guidance for the year, doubling its product sales expectations. It now anticipates product sales between $22 billion and $23 billion.
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