9. Biktarvy

In its second full year after approval in 2018, Biktarvy's sales increased 53%. With few challengers to pose a serious threat this year, expect another healthy sales bump in 2021 for Gilead's HIV treatment.

Company: Gilead Sciences
2020 sales: $7.26 billion
2019 sales: $4.74 billion
Used for: HIV

After making an incredible debut in its first full year on the market, what would Biktarvy do for an encore? 

How about a 53% increase in sales and a jump from No. 17 to No. 8 on the list of top-selling drugs?

It was a performance that far exceeded expectations–at least those of Evaluate Pharma, which pegged Biktarvy’s sales to swell by $1.6 billion. That estimated increase came up short by nearly $1 billion.

While Gilead is reaping the rewards of developing a talented prospect and then watching it overachieve, Biktarvy’s big numbers aren’t all gravy for the pharma giant. In fact, much of the success of Biktarvy has come at the expense of Gilead’s older HIV offerings.

RELATED: Gilead’s Biktarvy wins megablockbuster HIV nod, and rival GlaxoSmithKline strikes back

While sales of Biktarvy jumped by $2.52 billion in 2020, a significant chunk of that came from patients who switched from Gilead’s Truvada-based HIV products, which saw a combined drop of $1.93 billion. 

In the aggregate, Gilead’s HIV products accounted for $16.94 billion in sales in 2020. While that figure represented 69% of the company’s revenue, it was only a 3% increase in Gilead’s HIV revenue from 2019.

Biktarvy is a three-drug combo including novel integrase inhibitor bictegravir along with Gilead’s Descovy, which is a combo in itself between emtricitabine and tenofovir alafenamide. 

Also marketed as a solo HIV treatment, Descovy is on the rise, especially in the United States where sales jumped from $1.08 billion in 2019 to $1.53 billion last year, partly thanks to a new approval as pre-exposure prophylaxis, or PReP.

RELATED: U.K. marketing police slam Gilead for claiming Biktarvy tolerability beats GSK rival 

It wouldn’t be unreasonable to assume that Biktarvy’s future competition might come from inside the company. But there are other HIV treatments Gilead needs to be concerned with.

GlaxoSmithKline has been a major player in the HIV arena for two decades. Its joint venture with Pfizer and Shionogi, ViiV Healthcare, brings formidable challengers to market every few years. Its three-component drugs Triumeq and Tivicay generated a combined $3.8 billion last year, but that’s a decline from the $4.2 billion they made in 2019. Both are fading as Biktarvy gobbles up new customers.

ViiV is pinning its latest hopes on Dovato, a two-drug combo with better safety results which generated $374 million in sales in its first full year following its 2019 approval. ViiV also recently won approval for Cabenuva, a once-monthly injectable HIV treatment, but the company sees it as a niche treatment for people who struggle to stick to a daily regimen.

In other words, it’s a good time to be Biktarvy—unless and until ViiV’s rivals can gain more steam.

9. Biktarvy