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
Coronavirus Does Not Infect the Brain but Still Inflicts Damage
SARS-CoV-2, the virus that causes COVID-19, likely does not directly infect the brain but can still inflict significant neurological damage, according to a new study from neuropathologists, neurologists, and neuroradiologists at Columbia University Vagelos [...]
Research finds a potential new ‘silver bullet’ nanoparticle to treat brain cancer
ANSTO has contributed to a comprehensive investigation of a promising type of nanoparticle that could potentially be used for intractable brain cancers in a combined therapy. The study, which was led by Dr. Moeava [...]
Trial to study effect of immune system on Covid reinfection
The immune response needed to protect people against reinfection with the coronavirus will be explored in a new human challenge trial, researchers have revealed. Human challenge trials involve deliberately exposing healthy people to a [...]
Duke working on developing flu shot using new CoV vaccine technology
Researchers from Duke University are developing a flu shot with the new technology that was used for two coronavirus vaccines. Both the Pfizer-BioNTech and the Moderna shots use part of the virus's genetic code [...]
Long-acting injectable medicine as potential route to COVID-19 therapy
Researchers from the University of Liverpool have shown the potential of repurposing an existing and cheap drug into a long-acting injectable therapy that could be used to treat Covid-19. In a paper published in the journal Nanoscale, [...]
Superbug killer: New nanotech destroys bacteria and fungal cells
Researchers have developed a new superbug-destroying coating that could be used on wound dressings and implants to prevent and treat potentially deadly bacterial and fungal infections. The material is one of the thinnest antimicrobial [...]
US recommends ‘pause’ for J&J vaccine over clot reports
The U.S. is recommending a "pause" in administration of the single-dose Johnson & Johnson COVID-19 vaccine to investigate reports of potentially dangerous blood clots. In a joint statement Tuesday, the Centers for Disease Control [...]
S. African COVID variant better at bypassing Pfizer/BioNTech jab: Israeli study
The South African coronavirus variant is better at "breaking through" the defences of the Pfizer/BioNTech vaccine than other forms of the virus, Israeli experts said Sunday. However, one of the authors told AFP that [...]
Artificial intelligence to explore the biomolecular world
EPFL scientists have developed AI-powered nanosensors that let researchers track various kinds of biological molecules without disturbing them. The tiny world of biomolecules is rich in fascinating interactions between a plethora of different agents [...]
Why SARS-CoV-2 replicates better in the upper respiratory tract
A team of researchers from the Institute for Infectious Diseases (IFIK) at the University of Bern and the Federal Institute of Virology and Immunology (IVI) have assessed virus growth and activation of the cellular [...]
Brown University creates first wireless, implanted brain-computer interface
Researchers at Brown University have succeeded in creating the first wireless, implantable, rechargeable, long-term brain-computer interface. The wireless BCIs have been implanted in pigs and monkeys for over 13 months without issue, and human [...]
A New Generation of Vaccines Is Coming, Some With No Needles
The coronavirus outbreak made household names of companies like Moderna Inc. and BioNTech SE, whose shots offered hope for ending the pandemic. Now a new wave of vaccines is on the horizon that may get the [...]
Scientists use nanotechnology to detect bone-healing stem cells
Researchers at the University of Southampton have developed a new way of using nanomaterials to identify and enrich skeletal stem cells—a discovery which could eventually lead to new treatments for major bone fractures and [...]
Biotech start-up working overtime to develop a mutation-resistant Covid-19 vaccine
In March 2020, Hannu Rajaniemi pivoted his biotech company Helix Nanotechnologies' focus from cancer therapies to Covid-19 vaccines. The role biotech start-ups can play in a pandemic Rajaniemi originally co-founded Helix Nanotechnologies in Cambridge, Massachusetts in [...]
Nanotech-powered testing strategy can accelerate global recovery from pandemic
The rapid mass testing strategy costing just £1 a day per child can get children back to school and economies up and running, according to experts. That is the small price of the [...]
Nasal Spray Vaccine Could Be Key to Stopping the Spread of Covid-19
Covid-19 vaccines are incredibly good at preventing severe symptoms and hospitalization, but they’re probably less effective at stopping transmission. To do that, we might need a different kind of vaccine altogether. Because SARS-CoV-2 is [...]