COVID-19: Targeting Better Efficacy, China Trials Mixing CanSino and Zhifei Longcom Vaccines

Under the pressing need for more effective COVID-19 vaccinations, China has begun examining the efficacy of mixing two approved vaccines. The country is evaluating the combination of CanSino Biologics’ Ad5-nCoV (Convidecia) and Anhui Zhifei Longcom Biopharmaceuticals’ ZF2001 (RBD-Dimer).

Efficacy Evaluations in Two Interval Settings

Sponsored by the Jiangsu province centers for disease control and prevention in China, the trial recruited 120 healthy subjects who received one dose of Ad5-nCoV on day 0. Then, half of the subjects will receive a booster dose of either ZF2001 or trivalent split influenza vaccine on day 28 with the ratio of 2:1; the other half will be put under the same regime but with the interval of 56 days.

Scientists will primarily look at the incidence of solicited adverse events within 7 days after vaccination and geometric mean titer (GMT) of neutralizing antibodies against SARS-CoV-2 at day 14 after the booster vaccination. The trial will last for 6 months according to the clinical records on ClinicalTrials.gov.

Ad5-nCoV: 68% Efficacy with One Shot

Ad5-nCoV is the only single shot COVID-19 vaccine to be approved in China. As stated in the interim report of a Phase 3 clinical trial, the vaccine registered a 68.83% efficacy 14 days after administration. In 28 days, the number fell to 65.28%.

Currently, the vaccine is not approved in the US, but it has been granted accelerated approval in five countries, including China, Chile, Mexico, Pakistan, and Hungary. The five vaccines that are currently approved in China are all locally developed and produced.

CanSino Pushes for Inhaled Vaccine

According to Co-Founder and Chief Executive Officer Xuefeng Yu, CanSino Biologics is now working on an inhaled version of its COVID-19 vaccine with the help of the Beijing Institute of Biotechnology. An inhaled vaccine might add more protection than an injected one considering the airway is the first stop of SARS-CoV-2 entering the body. The clinical trial is expected to begin next week.

With that, CanSino Biologics will have a chance to compete with the global vaccine market since Pfizer/BioNTech, Moderna, AstraZeneca, and Johnson & Johnson vaccines demonstrated stronger protection than Ad5-nCoV.

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Author

Tyler Chen

"Never go to a doctor whose office plants have died."- Erma Bombeck