New York, May 30 (IANS): Global pharmaceutical major Pfizer believes that a vaccine to prevent Covid-19 could be ready by the end of October, the company's CEO Albert Bourla said.

Pfizer is conducting clinical trials in the US and Europe for the BNT162 vaccine programme to prevent Covid-19 in collaboration with German mRNA company BioNTech.

Bourla made the comments while participating at a virtual event organised by the International Federation of Pharmaceutical Manufacturers & Associations (IFPMA) this week.

"If things go well and the stars are aligned, we will have enough evidence of safety and efficacy for us to feel comfortable, for the FDA (US Food and Drug Administration) to feel comfortable, and for the EMA (European Medicines Agency) to feel comfortable, to have a vaccine around the end of October," Bourla was quoted as saying at the event by FierceBiotech.

Speakers at the event also included AstraZeneca CEO Pascal Soriot, GlaxoSmithKline chief Emma Walmsley, Johnson & Johnson Chief Scientific Officer Paul Stoffels.

Each of these companies are working with their partners to develop a vaccine to prevent the disease.

While GSK has joined forces with Sanofi, AstraZeneca is backing the vaccine being developed at the University of Oxford.

J&J is collaborating with the U.S. Biomedical Advanced Research and Development Authority to develop its vaccine.

So far over 120 vaccines have been proposed across the world. Currently, there are at least 10 candidate vaccines in clinical evaluation and 115 candidate vaccines in pre-clinical evaluation.

According to the WHO, it is important to evaluate as many vaccines as possible as we cannot predict how many will turn out to be viable.

To increase the chances of success, it is critical to test all candidate vaccines until they fail, the WHO said.

Pfizer and BioNTech's development programme includes four vaccine candidates, each representing a different combination of mRNA format and target antigen.

The novel design of the trial allows for the evaluation of the various mRNA candidates simultaneously in order to identify the safest and potentially most efficacious candidate in a greater number of volunteers, in a manner that will facilitate the sharing of data with regulatory authorities in real time.

"With our unique and robust clinical study program underway, starting in Europe and now the U.S., we look forward to advancing quickly and collaboratively with our partners at BioNTech and regulatory authorities to bring a safe and efficacious vaccine to the patients who need it most," Bourla said in a statement earlier this month.

"The short, less than four-month timeframe in which we've been able to move from pre-clinical studies to human testing is extraordinary and further demonstrates our commitment to dedicating our best-in-class resources, from the lab to manufacturing and beyond, in the battle against COVID-19," he added.

In anticipation of a successful clinical development programme, Pfizer and BioNTech are working to scale up production for global supply.

The breadth of this programme should allow production of millions of vaccine doses in 2020, increasing to hundreds of millions in 2021, Pfizer said.