Pfizer (PFE  ) revealed Wednesday it sold $7.8 billion worth of COVID-19 vaccines in the second quarter, leading the pharmaceutical giant to raise its 2021 sales forecast for the shot to $33.5 billion from $26 billion as the Delta variant continues to spread and health experts debate the need for booster shots.

"The second quarter was remarkable in a number of ways," Pfizer CEO Albert Bourla said in a press statement announcing the company's Q2 earnings. "Most visibly, the speed and efficiency of our efforts with BioNTech (BNTX  ) to help vaccinate the world against COVID-19 have been unprecedented, with now more than a billion doses of BNT162b2 (the pair's developed COVID vaccine) having been delivered globally."

Beyond vaccine sales, the company's Q2 financial results also beat Wall Street expectations on earnings and revenue. Pfizer's revenue of $18.98 billion was a year-to-year increase of 93% and beat estimates by $270 million. The company's earnings per share of $1.07 also beat by $0.09.

This earnings beat boosted exchange-traded funds that hold high percentages of Pfizer, including Invesco Dynamic Pharmaceuticals ETF (PJP  ), iShares U.S. Pharmaceticals ETF (IHE  ) and VanEck Vectors Pharmaceutical ETF (PPH  ), all rising over 1.5% on the day.

Following the quarterly earning beat, Pfizer now expects full year earnings in the range of $3.95 to $4.05 per share, up from its previous range of $3.55 to $3.65. It also expects revenue in the range of $78 billion to $80 billion, up from prior estimates of $70.5 billion to $72.5 billion.

Pfizer said earlier this month that it is seeing signs of declining immunity from its COVID vaccine in a recent study, and plans to seek Food and Drug Administration emergency authorization to use its first-generation vaccine as a booster shot to protect against the Delta variant. The company is also developing another booster shot with BioNTech to just target the highly transmissible strain.

At this time, the Centers for Disease Control and Prevention and World Health Organization do not recommend COVID vaccine booster shots, with the latter agency advocating for a more equitable distribution of vaccines globally.