Study: Experimental COVID shot made via egg-based technology elicits higher antibody proportion ...

[Jim__]

... than mRNA vax

My take on the importance of this is that this version of the vaccine can be produced locally and at low cost. The full study at Science is available here.

From MedicalXpress (Note: the purple bar in the charts is the bar for Pfizer's mRNA vaccine):

An experimental COVID-19 vaccine produced with technology based on a decades-old method, elicited virus-neutralizing antibodies in higher proportion than the amount induced by mRNA immunizations, a Phase 1 clinical trial has found.

The investigational vaccine was developed in New York City and tested in Thailand where the shots were produced using a form of egg-based technology. The fact that researchers are still racing to develop new COVID-19 vaccines highlights an ongoing need, especially in low- and middle-income countries—and for good reason.

A surprising slew of omicron subvariants has emerged since 2021. Last year, omicron spawned a dizzying number of subvariants: BA.5, BQ.1, and BQ.1.1. By January of this year, a new omicron subvariant called XBB.1.5 was sweeping across the United States and beyond.

"A large number of vaccines for SARS-CoV-2 have been developed and licensed," asserted Juan Manuel Carreño, writing with a team of researchers in Science Translational Medicine. As a research scientist in the microbiology department at Mount Sinai's Icahn School of Medicine in New York City where the vaccine was developed, Carreño underscored the need for effective and affordable COVID shots in overlooked regions of the world.

more ...

[Rebl2]

1. What if

A person is allergic to eggs. I would hope they keep the mRNA vaccine available.

[Jim__]

3. I don't think there is any intent to drop the mRNA vaccine.

From the study at Science:

A large number of vaccines for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been developed and licensed (1). Nevertheless, there is a need for SARS-CoV-2 vaccines that can be produced at low cost locally in low- and middle-income countries (LMICs). ...

Also, just my own thought, a lot of the people who won't take the mRNA vaccine refuse because it is new and there hasn't been any long-term testing. Maybe some of those people will take this alternative which is based on a long existing methodology.

[hlthe2b]

2. Reasons why flu vaccine grown in eggs is problematic (mammalian cells culture preferred)

and not just because of egg allergies that affect about 2% of children and persist in about half of adults that showed it in childhood.

Vaccines grown in eggs develop antibodies, not only to the organism targeted (e.g., flu virus) but to sugar molecule found in eggs, thereby shifting the antibody response intended and thus diminishing immunity. Further, a process known as egg adaptation can result in mutations in the target virus itself and ultimately diminished immunogenicity. This has been a major factor in flu vaccine failures--depending on the original circulating prominent virus type. For example virus effectiveness has been shown to be dramatically lower for egg-grown vaccines against influenza A (H3N2) than influenza A (H1N1) and influenza B viruses.
https://www.sciencedirect.com/science/article/pii/S1931312819302574


So, while egg-based COVID-19 viruses are possible it is not reasonable to think these same issues would not be at play--particularly given how mutation-prone these Coronaviruses have been shown to be. So, I don't see that as a likely path to better or even cheaper vaccines for the third world (mammalian cell culture MIGHT be an option, however).

[Duppers]

4. Good info.