Gilead Sciences (GILD) has seen its HIV franchise, led by Biktarvy, face a slowdown in growth momentum following strong returns over the past year. During an August 4, 2026 earnings call, management noted that growth in the HIV treatment market slowed in the second quarter, with Biktarvy sales rising only 7% year-over-year to $3.8 billion. This growth deceleration is attributed partly to a higher average price and inventory build rather than solely new patient demand, signaling a maturing market for the blockbuster drug. The financial implications of this slowdown are significant for Gilead's valuation and revenue trajectory. Biktarvy accounted for 48.7% of Gilead's fiscal 2025 revenue, contributing approximately $0.9 billion in sales that year. Analysts note that if Biktarvy had remained flat in 2025, it would have erased the company's overall sales growth, potentially causing total revenue to shrink given the high valuation multiple of 6.4 times sales compared to the S&P 500. Despite the HIV treatment slowdown, Gilead is finding growth in its HIV prevention business and maintains a strong balance sheet. Prevention sales doubled year-over-year in the second quarter, crossing $1 billion for the first time, driven largely by Descovy which grew 30.5% in fiscal 2025. The company generated $12.9 billion in free cash flow over the twelve months to June 2026 and expects full-year HIV sales growth of 9% to 10%, up from previous guidance. Investors are closely watching Gilead's upcoming third-quarter report expected on October 29 for confirmation of Biktarvy's growth rate and whether HIV sales meet the revised expectations. While the company has sufficient cash reserves to weather a slowdown in its primary revenue driver, the shift away from rapid expansion in HIV treatment poses a strategic challenge that could impact long-term stock performance if prevention growth does not fully offset the decline.