Despite its advantages over other vaccine technologies for Covid-19, adenovirus vector vaccines are likely to be tripped up by pre-existing antibodies to the vectors used and the need for a second injection to boost protection.
CanSino Biologics’ Ad5-nCoV and Johnson & Johnson’s AdVac platform-based vaccine use a human adenovirus vector, but a significant chunk of people may already have neutralising antibodies against the vector, decreasing efficacy prospects. Phase I Ad5-nCoV data is also underwhelming, adding credence to the issue of pre-existing antibodies.
AstraZeneca’s AZD1222 and Rome-based ReiThera’s Covid-19 vaccines are also adenovirus vectored but use nonhuman vectors. However, AZD1222’s recent animal data also leave questions about its utility to prevent virus spread. A possible way to improve efficacy is to add a booster shot down the line, perhaps using a different adenovirus vector or even a different vaccine technology. Perhaps AZD1222 only carrying SARS-CoV-2’s spike protein may not be enough.
There are at least 38 companies or universities with a recombinant adenovirus-derived vaccine asset for Covid-19 from preclinical to Phase II/III stages, according to GlobalData. AstraZeneca partnered with Oxford University on 30 April to further develop AZD1222, and on 3 June, the US Federal Government’s vaccine initiative, Operation Warp Speed, named it as one of five finalists along with Johnson & Johnson’s (J&J) candidate. Phase I/II AZD1222 trial (NCT04324606) data are expected shortly, while J&J’s Phase I/IIa will start in July. ReiThera will also begin a clinical investigation in the summer. CanSino is the only company that has released clinical trial data, with Ad5-nCoV already in a Phase II trial (NCT04341389) that has a primary completion date of January 2021.
AZD1222 is concurrently in Phase II/III trial (NCT04400838), with data timelines dependent on community viral transmission rates, the Oxford University website states. A registrational field trial expected to start in the summer is likely to require around 25,000–30,000 volunteers if the annualised incidence rate is 1.5%, this news service reported on 14 May. While a challenge trial design could be considered to quickly gather protection data, such a trial design also has its own operational and ethical issues.
Image Credit: Envato/ Amanda Scott
News This Week
For the past several months, Omicron subvariants BA.4 and BA.5 have dominated COVID-19 cases in the U.S. But now, there’s a class of new COVID subvariants on the rise and one in particular is getting plenty of [...]
Nucleic acid therapies involving DNA or RNA have significant potential to treat genetic disorders, infectious diseases, and cancer; however, research suggests that less than 1% of injected nucleic acid doses reach target cells in [...]
The US Food and Drug Administration on Tuesday approved Hemgenix, a new drug to treat hemophilia. Manufacturer CSL Behring set the price at $3.5 million per treatment, making it the most expensive drug [...]
Some wounds just won’t heal. Infections, diseases like diabetes, and suppressed immune systems often stack up to slow healing. Chronic wounds can last months and lead to anxiety and depression. In the worst cases, [...]
Over the years, researchers have tried hard to comprehend topographic signals that promote cell mechanical sensitive responses. The extracellular matrix (ECM) provides a complex cellular microenvironment that controls cellular behavior. Nevertheless, only a few [...]
There is now an imminent threat of measles spreading in various regions globally, as COVID-19 led to a steady decline in vaccination coverage and weakened surveillance of the disease, the World Health Organization (WHO) [...]
In a recent study, it was shown that people with long Covid have had physical changes to their brains several months after experiencing the initial infection. The study included MRIs of patients who continued [...]
Western University in London, Ont., is building a unique research lab to study humanity's greatest viral threats — a secret weapon, if you will, one that it's expected would put Canada and the world in a better position if [...]
Cancer patients are testing a medicine made of antibodies that were designed from scratch on a computer in Israel and whose inventor has “programmed” them to “decide” whether cells surrounding tumors are bad or good. [...]
In an article published in the journal Scientific Reports, researchers presented the potentiostatic deposition used to electrodeposit nickel (Ni) and nickel-graphene (Ni-G) films on copper substrates. Myristic acid (MA) was employed to alter the plane of the [...]
Oregon State University scientists have invented a way to make magnetic nanoparticles that get hotter than any previous nanoparticle, improving their cancer fighting ability. Faculty from the OSU College of Pharmacy spearheaded a collaboration [...]
November 14, 2022 -- Researchers at the University of Texas MD Anderson Cancer Center have developed a nanotechnology platform that changes the immune system's perception of solid tumor cells, making them more receptive to immunotherapy. [...]
Nanotechnology platform enables immune conversion of cancer cells, sensitizing them to immunotherapy
A team of researchers at The University of Texas MD Anderson Cancer Center has developed a nanotechnology platform that can change the way the immune system sees solid tumor cells, making them more receptive [...]
Researchers learn to engineer growth of crystalline materials consisting of nanometer-size gold clusters
First insights into engineering crystal growth by atomically precise metal nanoclusters have been achieved in a study performed by researchers in Singapore, Saudi Arabia and Finland. The work was published in Nature Chemistry ("Supercrystal engineering of [...]