Pfizer CEO Albert Bourla on Sunday said there is a “good chance” the pharmaceutical company—which is one of the several developing a COVID-19 vaccine—will know the efficacy of its immunization sooner than expected.

Appearing on told CBS Face the Nation, Bourla claimed there is a more-than-60% chance Pfizer will be able to confirm whether or not its vaccine is effective by end of October. At that point, distribution would depend on FDA approval, he added. Elsewhere on the same show, former FDA commissioner Dr. Scott Gottlieb—a member of Pfizer’s board—cautioned that any vaccine would not be widely available until 2021, with a “staged market entry” taking place.

Pfizer is reportedly the only American pharmaceutical company that has rejected federal funding in hopes of avoiding accusations of any political conflicts of interest. In advance, however, Bourla said Pfizer has already begun manufacturing “hundreds of thousands” of doses in the event of speedy approval and rollout.

“We are almost done with 30,000 people. Now we feel quite comfortable with the safety of the product,” he told CBS host Margaret Brennan, with hopes of expanding Phase-3 vaccine trials to include more people of color and from other vulnerable populations now that its safety is better established.