Will chicken eggs change the Covid-19 vaccine landscape?

WEEKLY INSIGHTS

Will chicken eggs change the Covid-19 vaccine landscape?

Author: Andrea Taylor

A promising new vaccine candidate is getting a flurry of attention this week, even in a very crowded landscape that includes 11 vaccines on the market and 50+ more in Phase 2 or 3 trials. The newcomer NDV-HXP-S vaccine, developed through collaborations between researchers at University of Texas at Austin, PATH, and Mount Sinai, among others, is a mouthful to say but the name captures the two reasons people are excited about it.

NDV refers to the Newcastle Disease Virus, a disease that effects birds but does not harm people. Using NDV as a viral vector for vaccines means the vaccine can be developed in chicken eggs, as is commonly done for the flu vaccine. NDV has also been used as a vector for vaccines against SARS 1, RSV, and Ebola.

HXP stands for HexaPro, a spike protein developed by researchers in the US that is stronger than the protein used by the vaccines currently on the market. This means it can work well in difficult climates. Several of our current Covid-19 vaccines (we’re looking at you, mRNA) are divas – extremely difficult to manufacture and difficult to transport. The HexaPro protein was designed to be rugged and easy to make without falling apart, intentionally created with lower-income markets in mind.

The NDV-HXP-S vaccine candidate is being eyed as a potential gamechanger for several reasons:

• Manufacturing: Many low- and middle-income countries (LMICs) already have expertise in making flu vaccines using chicken eggs and could apply this to making Covid-19 vaccine. And manufacturers in 80 LMICs can use HexaPro without paying royalties, thanks to a licensing agreement with University of Texas. This means countries such as Brazil and Thailand could own the manufacturing of this vaccine from start to finish.
• Cost: Experts estimate that it could be produced for as little as $0.50 to $1 per dose, which would make it the cheapest Covid-19 vaccine by far.
• Scale: Production can be scaled up very quickly, using existing infrastructure. The vaccine is so potent, that each egg can provide enough for 5 to 10 doses (typically flu vaccine gets 1 to 2 doses per egg).

This is not going to be a quick fix, however. The vaccine candidate is just beginning Phase 1/2 clinical trials in Brazil, Thailand, Vietnam, and Mexico (all of which also have the capacity to make it). If all goes well, it could potentially enter Phase 3 trials by late summer and, if effective and safe, start production by end of 2021 at earliest.

But most of the world will still be waiting for vaccines at the end of this year so this may still come in time to supply LMICs. It could also put us a much better position for global equity if boosters are needed.

To serve LMICs, a vaccine needs to be effective, affordable, available, and easy to transport. This vaccine looks like it can tick three of those boxes so far. We will have to wait on clinical trial results to see if it can tick all four.

INTERESTING TRENDS

Significant updates, news, and trends we saw last week:

• We’ve posted a new visualization on our procurement webpage this week that shows how many doses per person have been purchased by each country, differentiated by country income category. (Note that to allow an apples-to-apples comparison, we doubled the single-dose vaccines Janssen and CanSino for this visualization.)  
• Indian manufacturer Panacea Biotech has signed up to manufacture the Sputnik V vaccine for global supply, with capacity to make 100 million doses per year.
• The University of Oxford has launched a Phase 1 trial to test the Oxford-AstraZeneca vaccine delivered as a nasal spray, rather than injection.
• The European Medicines Agency (EMA) is investigating reports of blood clots stemming from the Janssen (J&J) vaccine.
• Pfizer and BioNTech filed for EUA expansion to include adolescents (12-15 years old) in the US. The companies plan to request expansion approvals across the world in the near future.
• Many countries are restricting use of the Oxford-AstraZeneca vaccine in younger people, as a potential connection with rare blood clots (and now a bleeding disorder) are further investigated. In Europe, Italy, Spain, Belgium, Germany, the Netherlands, France, Finland, Sweden and the UK have required or recommended that the shot be used only for older age groups. Canada, Australia, and the Philippines have followed suit.
• Supply of the Janssen (J&J) vaccine in the US is expected to drop by 80% this week, though the reasons are unclear. The company says it is still on target to deliver 100 million doses to the US by midyear.
• The Biden administration in the US has appointed Gayle Smith to a new State Department role leading the US response to Covid-19 globally. Ms. Smith is the CEO of the ONE campaign and previously served as USAID administrator; she has advocated for vaccine donations and a more coordinated international response to support lower-income countries.
• However, an article this week in Vanity Fair explores how and why the US may be contractually restricted from sharing surplus doses with other countries.
• Last week, we noted that the Emergent BioSolutions facility in Baltimore accidentally mixed ingredients for the Oxford-AstraZeneca and Janssen (J&J) vaccines, invalidating a batch of Janssen vaccine. Emergent’s facility will now only manufacture Janssen and the manufacture of Oxford-AstraZeneca will be relocated.
• Serum Institute of India (SII) asked the government of India for $400 million to help increase production to relieve its “very stressed” capacity. SII is the primary supplier of doses for COVAX and many LMIC markets but India’s recent export controls have delayed shipments out of the country.
• Despite the stress on SII’s production capacity and resulting delays to COVAX and LMIC supply, the EU asked if they could possibly get 10 million doses of Oxford-AstraZenca vaccine from SII to make up for the shortfall from European manufacturers. The UK made a similar request earlier this year and received half of their order from SII. 
• African Union and Africa CDC are hosting a two-day conference on “Expanding Africa’s Vaccine Manufacturing,” April 12 and 13. 
• The US will host a (virtual) event on April 15 bringing together private- and public-sector leaders to make the case for additional investment in the COVAX AMC to support access to Covid-19 vaccines for lower-income countries.

For more information on our research on Covid-19 vaccine supply, please see https://launchandscalefaster.org/COVID-19.