Pfizer says BNT162b2 vaccine is effective against new Covid strains


2021-01-13 05:31:11 pharmbr


Pfizer and BioNTech said that their Covid-19 vaccine BNT162b2 has been found to be effective against a key mutation found in two highly transmissible strains of the SARS-CoV-2 virus as per the results from an in vitro study. The in vitro study, which was held by Pfizer and the University of Texas Medical Branch (UTMB), demonstrated that the antibodies from people subjected to the vaccine could effectively work against the rapidly spreading variants. Reported initially in the UK and South Africa, the Covid-19 variants have multiple mutations in their spike or S glycoproteins, which are main targets of virus neutralising antibodies, said Pfizer. According to the US pharma major, although, the two rapidly spreading variants are different, they share the N501Y mutation located in the receptor binding site of the spike protein. The N501Y mutation helps in the spike protein of the SARS-CoV-2 virus to bind more tightly to its receptor, said Pfizer. The company revealed that for determining if sera of people who were given the BNT162b2 can neutralise SARS-CoV-2 with the N501Y mutation, a virus with the substitution was created in UTMB’s laboratory. It was found that the sera of 20 participants from the previously held phase 3 trial neutralised the SARS-CoV-2 virus with the N501Y mutation apart from neutralising the virus without the mutation. Pfizer said that the key N501Y mutation does not provide resistance to the immune responses induced by the BNT162b2 vaccine. The company stated: “Pfizer, BioNTech, and UTMB are encouraged by these early, in vitro study findings. Further data are needed to monitor the Pfizer-BioNTech COVID-19 vaccine’s effectiveness in preventing COVID-19 caused by new virus variants. “If the virus mutates such that an update to the vaccine is required to continue to confer protection against COVID-19, we believe that the flexibility of BioNTech’s proprietary mRNA vaccine platform is well suited to enable an adjustment to the vaccine.” The BNT162b2 vaccine has been authorised to be used across multiple countries including the US under emergency use for providing protection against the SARS-CoV-2 virus that causes Covid-19. Last month, Pfizer and BioNTech signed a deal with the US government to supply an additional 100 million doses of the BNT162b2 vaccine.
辉瑞公司和BioNTech公司表示,根据一项体外研究的结果,他们的Covid-19疫苗BNT162b2已被发现对在两种高度传播的新型冠状病毒病毒株中发现的一个关键变异有效。 这项由辉瑞公司和德克萨斯大学医学分部(UTMB)联合进行的体外研究表明,接种疫苗的人产生的抗体能够有效地对抗快速传播的变异体。 辉瑞公司说,最初在英国和南非报道的Covid-19变异体在其spike或S糖蛋白上有多个突变,这些糖蛋白是病毒中和抗体的主要靶点。 根据美国制药学专业,虽然,这两个快速传播的变异体是不同的,但它们共享位于穗蛋白受体结合位点的N501Y突变。辉瑞公司说,N501Y突变有助于新型冠状病毒病毒的尖峰蛋白更紧密地与其受体结合。 该公司透露,为了确定给予BNT162b2的人的血清是否能够中和带有N501Y突变的新型冠状病毒病毒,UTMBS实验室制造了一种带有这种替代的病毒。 研究发现,在先前进行的第3阶段试验中,20名参与者的血清除了中和未发生突变的病毒外,还中和了带有N501Y突变的新型冠状病毒病毒。 辉瑞公司表示,关键的N501Y突变不提供对BNT162b2疫苗诱导的免疫应答的抵抗力。 该公司表示:辉瑞,BioNTech和UTMB对这些早期的体外研究结果感到鼓舞。需要进一步的数据来监测Pfizer-BioNTech COVID-19疫苗在预防新病毒变种引起的COVID-19疫苗方面的有效性。 如果病毒发生变异,需要对疫苗进行更新以继续提供针对COVID-19的保护,我们相信Biontechs专有mRNA疫苗平台的灵活性非常适合于对疫苗进行调整。 BNT162b2疫苗已被授权在包括美国在内的多个国家紧急使用,以提供针对引起Covid-19的新型冠状病毒病毒的保护。 上个月,辉瑞和BioNTech与美国政府签署了一项额外供应1亿剂BNT162b2疫苗的协议。