Professor Ugur Sahin, co-founder and chief executive of BioNTech, also suggested the vaccine could halve transmission of the virus, resulting in a "dramatic reduction" in the number of reported cases.
Last week, Pfizer and BioNTech said an early analysis of their vaccine candidate showed it was more than 90% effective in preventing Covid-19 infections among those without evidence of prior infection.
Approximately 43,500 people took part in the tests.
The vaccine efficacy was significantly higher than scientists had been expecting, prompting Pfizer Chairman and CEO Dr. Albert Bourla to declare the development: "A great day for science and humanity."
Huge challenges remain before a vaccine can be rolled out, but the news raised expectations that one could be delivered perhaps even before the end of the year.
It is hoped a vaccine could help bring an end to the coronavirus pandemic that has claimed more than 1.31 million lives worldwide.
"This winter will be hard. So, we will not have a big impact on the infection numbers with our vaccine in this winter," BioNTech's Sahin told the BBC's "Andrew Marr Show" on Sunday.
"If everything continues to go well, we will start to deliver the vaccine end of this year, beginning (of) next year. Our goal is to deliver more than 300 million of vaccine doses until April next year which could allow us to already start to make an impact."
Sahin said it was "absolutely essential" to complete immunizations before next fall.
"I'm confident that this will happen because there are a number of vaccine companies helping us to increase the supply and so that we could have a normal winter next year."
White House coronavirus advisor Dr. Anthony Fauci said last week that while a vaccine appeared to be on the horizon, it may not be enough to eradicate the disease.
"I think we need to plan that this is something we may need to maintain control over chronically. It may be something that becomes endemic, that we have to just be careful about," Fauci said during a webinar hosted by think tank Chatham House.
"Certainly, it is not going to be a pandemic for a lot longer because I believe the vaccines are going to turn that around."
The comments come amid an upsurge of coronavirus infections in Europe and the U.S. that shows no sign of slowing.
Several countries in Europe have implemented national lockdowns to try to curb the spread of the virus, while a number of U.S. states have also recently moved to impose tougher public health measures as infections continue to rise.
The U.S. has now recorded more than 11 million cases of the coronavirus, with 246,217 related deaths, according to data compiled by Johns Hopkins University.
The U.S., the country with the highest number of reported Covid-19 cases worldwide, diagnosed its first coronavirus infection in Washington state on Jan. 20. It surpassed 10 million cases on Nov. 9 and hit the 11 million mark just seven days later.
When asked whether the vaccine was as effective in older people as it is in younger people, BioNTech's Sahin said the German biotech firm would have a clearer understanding of this in the next three weeks.
He said it was not yet known how long immunity would last after the second of two vaccine doses was given.
A booster immunization should not be "too complicated," Sahin said, if it was found immunity reduced significantly after one year.
Some of the side effects of the Pfizer-BioNTech vaccine reported so far included a mild-to-moderate pain at the injection site for a few days, Sahin said, while some participants had a mild-to-moderate fever over a similar time frame.
"As a scientist and from extrapolation of what we have seen so far for other viruses, I would expect that a high efficacy in preventing disease translates into at least some efficacy in preventing infection," Sahin told the BBC on Sunday.
"So, I'm very confident that transmission between people will be reduced by such a highly effective vaccine – maybe not 90% but maybe 50%. But we should not forget that even that could result in a dramatic reduction of the pandemic spread."
The Pfizer-BioNTech vaccine is one of several in the final stages of testing, as drugmakers and research centers worldwide scramble to deliver a safe and effective vaccine.