Top 5 reasons Harvoni and Sovaldi may be in trouble

While sales of Gilead Science’s popular hepatitis C drug, Harvoni, had been performing well for several months, the trend has reversed of late. Hepatitis C drug Sovaldi, also from Gilead, has also hit some bumps in the road – in both the United States and China.

Related:FDA warns about serious reactions to Harvoni, Sovaldi

Here are the top 5 reasons that Harvoni and Sovaldi may be in trouble:

• For the week ending June 12, the new prescription volumes for Harvoni showed a decline compared to the previous week, according to new prescription data from RBC’s Michael Yee and John Chung. While the total prescriptions for Harvoni rose 2% to 9,133, new prescriptions declined 1% to 3,317.

• Since its launch last October, Harvoni prescriptions continued to grow monthly. However, that trend reversed starting in March. “Harvoni + Sovaldi NRx have been decelerating since last week of March – WK April sales also showed decline in monthly sales for first time,” Yee and Chung wrote in the report, according to Barron’s.

• The analysts’ 2015 sales forecast for Harvoni and Sovaldi was slightly below the consensus estimate at $11.7 billion. The projected sales are still impressive, with Harvoni expecting to bring in $10.2 billion this year and Sovaldi to produce $1.5 billion.

• There was bad news for Sovaldi last week when China invalidated its patent for Sovaldi. “Approximately 29 million people are affected by HCV in China, and analysts had predicted that Gilead could offer Sovaldi at a discounted rate of $2,000 for a 12-week treatment course to the large patient population in the country,” according to a recent Bidness Etcarticle.

• Even as Harvoni scripts are declining, prescription volumes for AbbVie’s Viekira Pak, are on the rise. Even though Viekira Pak sales started slow this year – the company reported $231 million in worldwide sales in the first quarter, with $138 million of that attributed to US sales – the hepatitis C medication is expected to produce $3 billion in global sales by the end of 2015, according to AbbVie executives.

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