Another Intranasal Covid Vaccine Starting in the US (NextGen Vax Monthly Update)

This month intranasal and inhaled versions of a Covid vaccine are heading into a phase 1 trial in the US. The vaccine was developed in the US, and a company has already rolled out a version of this vaccine in India. Another trial for an intranasal vaccine is now recruiting from an extra 2 cities, and a trial for a “variant-proof” vaccine has expanded in Germany. There are also 3 preclinical reports for “variant-proof” vaccines.

This post begins with my watchlist of next generation Covid vaccines advancing into mid- or late-stage trials. There are 9 vaccines in this list, with no updates for them this month. After that, I have vaccine news broken down into the usual 3 categories of next-generation vaccines (definitions below). Each section ends with an overview of vaccines in the category – and each has a link to skip over that straight to the next news section. In addition, there are tables tracking mucosal vaccine trials and pancoronavirus vaccines on my personal website. (This is the 40th of my updates on next generation Covid vaccines.)

ICYMI:

• An introduction to self-amplifying mRNA, plus my compendium on getting ready for more mRNA fear-mongering.
• Check out my May 2024 post, “When will we get a sterilizing Covid vaccine?”

• Watchlist of featured vaccines
• Mucosal vaccine news
• Durable or “variant-proof” vaccine news
• Pancoronavirus vaccine news

• Addendum 1: List of authorized vaccines (with countries)
• Addendum 2: Definitions of vaccine types
• Addendum 3: Table of mucosal vaccines in clinical trials (here—off this blog)
• Addendum 4: Table of pancoronavirus vaccines with preclinical results (here—off this blog)

• Postscript: US Project NextGen funded trials

Watchlist of featured vaccines

There are no updates to this section this month. (Click here to skip ahead to next section.)

This watchlist includes vaccines in advanced development, which currently appear to be progressing more than others, based on publicly available information. I have sorted them into several groups, starting with the most advanced prospects. Which vaccines make this list is very likely to change from month to month. For example, the Arcturus self-amplifying mRNA vaccine is not on this list, even though additional authorizations have been planned for it internationally. That’s because the impact of changes in the US have set it back, and there hasn’t been an update about the implications for further rollout.

I am currently featuring 9 vaccines:

[A] Vaccines in mid- to late-stage trials, with manufacturing partners or planned production facilities—3 vaccines (including 1 mucosal) from Japan, the US, and South Korea (VLP Therapeutics, Vaxart/Dynavax, DV&VX);

[B] A vaccine in advanced mid-stage trials—for people with immunocompromise, from the US (Geovax);

[C] A vaccine adapted from a Covid vaccine that has already been approved in South Korea (SKYCovione); and

[D] Vaccines in mid-stage trials with recent public progress—4 vaccines (all mucosal) from Canada, the US, and France.

A. Vaccines in mid- to late-stage trials with manufacturing prospects:

Self-amplifying mRNA vaccine from VLP Therapeutics Japan:

This development program has been moving rapidly, adapting the vaccine to emerging variants in Japan. It is a self-amplifying mRNA vaccine, which can be more durable than first-generation mRNA. (My explainer on this vaccine type here.) The developer, VLP Therapeutics, is based in the US and Japan. They have been receiving funding support from the Japanese government for this vaccine, and I do not know if there are plans for making the vaccine available in other countries. VLP Therapeutics has also received private backing, developing manufacturing facilities in Japan.

I’ve listed all the clinical trials for this vaccine in the following table. VLPCOV-1 targeted the original strain of Covid, VLPCOV-2 was adapted for the Gamma variant, and versions 4 and 5 were adapted to Omicron variants.

Results have been published for a phase 2 trial of VLPCOV-2, which was compared to an Omicron-adapted version of the BNT/Pfizer vaccine. The VLP vaccine had similar results, even though it had the disadvantage of not being adapted to Omicron.

At the end of March, a phase 1 trial was registered for a “universal” Covid version of the vaccine. This latest version of the vaccine is called VLPCOV-U-1, and it is a T-cell-inducing vaccine aimed at a part of the virus that has not mutated in new Covid variants. T-cell-inducing vaccines don’t rely on developing antibodies, but develop T-cells to eliminate virus-infected cells.

Over 10,000 people have been recruited to phase 3 trials for the Omicron versions. Given the speed at which this development program has been moving, it might not be long until we get the first phase 3 trial results.

(All records in my collection for this vaccine here.)

Phase	Trial status	Participants	Register record	Results reported
VLPCOV-1
1	Begun 2021; completed.	Booster dose in 45 adults.	jRCT2071210067
1	Begun 2022; completed.	Booster dose in 92 adults.	jRCT2051210164	August 2023
2	Begun 2022; fully recruited.	Booster dose in 300 adults.	jRCT2051220087
VLPCOV-2
1/2	Begun 2023; completed.	Booster dose in 96 previously vaccinated adults (phase 1); 323 adults in phase 2.	jRCT2051230005	February 2024 (Phase 1) February 2026 (Phase 2)
VLPCOV-4
3	Begun 2023; fully recruited.	Booster dose in 2,000 adults.	jRCT2051230141
3	Begun 2024; fully recruited.	Booster dose in 2,000 adults.	jRCT2051230178
VLPCOV-5
3	Begun 2025; fully recruited.	Booster dose in 6,200 adults.	jRCT2031240751
VLPCOV-U-1 (“Universal” Covid)
1	Begun 2026; recruiting in Japan.	Booster dose in 80 adults.	jRCT2051250250

Oral viral vector vacccine from Vaxart and Dynavax (USA):

This mucosal vaccine comes in tablets, and it is based on an adenoviral vector. Vaxart expects to release the 12-month results for the first 400 people in its large phase 2b trial by the middle of this year, with the first results for the other 5,000 people by the end of the year. Late last year the company announced that, pending positive phase 2b results, Dynavax will be their global manufacturing partner. Then at the end of year, drug manufacturing giant Sanofi acquired Dynavax.

I’ve listed their clinical trials in the following table. They have released so far from their phase 2a trial so far, indicating that the vaccine induced additional mucosal immunity in people who had previously been vaccinated with mRNA.

(All records in my collection for this vaccine here.)

Phase	Trial status	Participants	Register record	Results reported
1	Begun 2020; completed.	Booster dose in 40 adults.	NCT04563702	July 2022
2a	Begun 2021; completed.	Booster dose in 66 adults.	NCT05067933	Brief report: September 2022 press release.
2b	Begun 2024; fully recruited.	Booster dose in 5,400 adults.	NCT06672055	(Expected in late 2026.)

Virus-like particle vaccine from Stanford University and DX&VX (USA, South Korea):

DV&VX announced that they are accelerating this vaccine’s development, planning to start a global phase 2 trial early this year. They have indicated interest in developing a mucosal version of the vaccine. It’s a ferritin-based virus-like particle vaccine, using nanoparticles to modify the proteins.

The developers at Stanford aimed for a low-cost vaccine stable at room temperature, that would not be vulnerable to changing Covid variants—another “universal” Covid vaccine. It is also expected to have yearly boosters.

Their clinical trial program is in the table below.

(All records in my collection for this vaccine here.)

Phase	Trial status	Participants	Register record	Results reported
1	Begun 2023; completed.	Booster dose in 121 adults (USA).	NCT05870839
1	Begun 2023; completed.	Booster dose in 130 adults (South Africa).	NCT05938075
2	(Expected in early 2026.)

B. Vaccine in advanced mid-stage trials:

Viral vector vaccine for people with compromised immune systems, from the City of Hope and Geovax

This is the only advanced next generation Covid vaccine designed for better protection of people with immunocompromise and others at high Covid-risk. (Arcturus is also running a phase 2 trial of their self-amplifying mRNA vaccine.) This is one of the vaccines that faced a setback when the US government canceled Project NextGen support. Geovax has reported that it is seeking partners to take the vaccine forward.

The City of Hope/Geovax vaccine has outperformed mRNA vaccine in people with immunocompromised in their trials: a table of their trials follows. The viral vector is modified Ankara virus (MVA).

(All records in my collection for this vaccine here.)

Phase	Trial status	Participants	Register record	Results reported
1 to 2	Begun 2020; completed Dec 2025	Booster shot (escalating doses) in 119 healthy adults	NCT04639466	Phase 1 (56 participants)
2	Begun 2021; fully recruited.	2 dose regimen in 63 adults with blood cancer who have received stem cell transplant or cellular therapy (compared with mRNA vaccine)	NCT04977024
2	Begun 2023; still recruiting for experimental arm only.	1 dose in 80 adults with chronic lymphocytic leukemia (CLL) (initially compared with mRNA vaccine, but control group discontinued because of lack of effect)	NCT05672355

C. Adapted version of an already-approved vaccine:

Protein subunit unit pancoronavirus vaccine from SK Bioscience (South Korea)

A phase 1/2 trial for 368 participants has only just started for this vaccine in Australia. However, as it is an adapted version of a Covid vaccine that had already achieved authorization (marketed for a time as SKYCovione), it begins with the advantage of an established research base that may speed it up down the line.

This vaccine was originally developed by the University of Washington in Seattle. The original vaccine was shown to provide some protection against other sarbecoviruses in animals, leading to the development of a pancoronavirus version of the vaccine.

(All records in my collection for the original version of this vaccine here, and for the pancoronavirus version here.)

D. Vaccines in mid-stage trials with recent public progress:

There are 4 mucosal vaccines in this group, that have yet to announce manufacturing partners:

• Aerovax: This aerosolized viral vector vaccine (adenovirus) is being developed by McMaster University in Canada. The phase 2 trial began recruiting participants in March 2025, and is still recruiting at McMaster. (All records on this vaccine here.)

• Castlevax: This intranasal viral vector vaccine (Newcastle disease) has been authorized in some countries in injected form. The vaccine was developed by the Icahn School of Medicine at Mt Sinai in New York. The phase 2 trial began dosing participants in November 2025, and is recruiting in Colorado and Massachusetts. (All records on the US development of this vaccine here.)

• CyanVac and Blue Lake Biotech: This is an intranasal viral vector vaccine (parainfluenza), and it was developed at the University of Georgia. A phase 2b trial for this vaccine was fully recruited by November 2025. (All records on this vaccine here.)

• University of Tours and LovalTech: This is an intranasal protein subunit vaccine, developed with French government support. Phase 1 of a phase 1/2 trial finished dosing in May 2025, and LovalTech is seeking additional financial support: Phase 2 may not begin this year.

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Mucosal vaccine news

This month, a new phase 1 trial for an intranasal and inhaled vaccine is on the starting blocks in the US, and another has expanded. In other news, the international human challenge consortium for mucosal vaccines, MUSICC, had its third international meeting this month. I haven’t seen any reports of proceedings.

Intranasal vaccine trial news

• The phase 1 trial for the viral vector vaccine called OCU500 has been registered in the US, with 5 locations listed. Recruiting has not started, but contact details are here. Intranasal and inhaled versions will be tested, in 80 people. The vector for this vaccine is chimpanzee adenovirus (ChAd), and it is the vaccine that was developed by the University of Washington St Louis. It is the vaccine rolled out by Bharat Biotech in India, with intranasal application (called iNCOVACC). In the US, a company called Ocugen has licensed the vaccine. The trial is being run by the NIH’s NIAID, following a Project NextGen grant.
  
  (See all records for the developing in the US, and all records for the intranasal version in India.)

• The NIAID/NIH trial for an intranasal fusion protein vaccine called BOOST-2867 has expanded recruiting to a further 2 cities, bringing the total to 8. The new cities are Rochester and Durham. (Contact details here.)

Skip ahead to next news category

Mucosal Covid vaccine overview

• 5 mucosal vaccines are currently authorized for use, at least 1 in each of 6 countries. None have been authorized by a drug regulatory agency designated stringent, or listed, by WHO. However, each has been authorized by a regulator which has transitional WHO listing for vaccines.
• 36 mucosal vaccines have reached clinical trial, although some of the vaccines are no longer in development. The vaccines that have entered clinical trials are tracked in a table below. They are mostly viral vector vaccines.
• In addition to the 5 authorized mucosal vaccines, 6 have reached phase 2 trials, and another 2 have reached phase 2/3 trial.

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Durable or “variant-proof” vaccines

This month, there were 3 preclinical reports for vaccines in this category, and a phase 1 trial for another vaccine has expanded into phase 1/2a.

In addition, last November I reported on a preprint of additional antibody results from a phase 3 trial for Kostaive, the self-amplifying mRNA vaccine from Arcturus (USA). The study explored why responses were more durable for the self-amplifying mRNA than for the comparison mRNA vaccine (BNT/Pfizer). These results have now been published in a journal. (All records in my collection for this vaccine here.)

Expansion of trial for Prime-2-CoV_Beta, a viral vector vaccine from Speransa Therapeutics and the University of Tübingen (Germany)

The viral vector for this vaccine is orf, a type of poxvirus. After the first phase 1 trial for this vaccine, the developers concluded that a higher dose was needed, and they began a second phase 1 trial. They concluded again that the safety and immune response data were positive, but a higher dose still was worth testing. That trial has now been expanded to a phase1/2a trial for 96 participants, with new arms for higher doses. The developers are recru8iting for participants in Hamburg and Tübingen. (Contact details here.)

Preclinical reports

• Viral vector and DNA-launched self-amplifying RNA vaccine pair from the National Center of Biotechnology (CNB-CSIC) (Spain): I have reported several times on this viral vector vaccine. The CNB-CSIC vaccine is based on modified virus Ankara (MVA). It has been tested in several preclinical studies in both intramuscular and intranasal versions, and in combinations of injected versions with intranasal versions of the Mt Sinai-developed viral vector vaccine, NDV-HXP-S (based on Newcastle disease virus). (All records on the MVA vaccine in my collection here.)
  
  In this new study, the group developed a vaccine using DNA vaccination to launch self-amplifying RNA (DREP). They compared 2 doses of the DREP vaccine, 2 doses of MVA, or a dose of DREP with an MVA booster in mice. There were 2 versions of each vaccine: One based on the original strain of SARS-CoV-2, and one based on an Omicron variant (XBB.1.5). Each regimen with an MVA booster elicited stronger responses, with the DREP/MVA regimen having a stronger earlier response. MVA vaccination showed minimal waning at 6 months.

• Viral vector vaccine from the Laval University (Canada): This is the second preclinical report for this vaccine. (The first is here.) It is based on papaya mosaic virus. Two versions of the vaccine were tested in mice, including a challenge test with the original strain of SARS-CoV-2. Both versions reduced viral load in the challenge test, and animals showed immune responses to the Omicron variant.

• Virus-like structure mRNA vaccine from Weirui Biotechnology (Kunming) and Shandong Weigao Litong Biological Products (China): This vaccine uses mRNA and proteins to mimic the SARS-CoV-2 virus. This is the second report for this vaccine. (The first is here.) It was tested in mice and hamsters, including challenge tests—the original SARS-CoV-2 strain in hamsters, and 2 variants in mice. The developers concluded that the vaccine mimicked infection pathways, and provided broad protection and immune responses.

Skip ahead to next news category

Durable or “variant-proof” vaccine overview

Note: This is a rather vague category, including vaccines that aim to be more durable. I’m not sure how many can be classified as aiming to be “variant-proof”.

Authorized vaccine:

There is 1 authorized vaccine in this category, and it has been authorized by several drug regulatory authorities designated by WHO has stringent, and tested against an mRNA vaccine (Kostaive):

• LUNAR-COV19 (USA), trade name Kostaive: This self-amplifying mRNA vaccine was authorized in Japan in November 2023, with rollout in October 2024. It was authorized for Europe in February 2025, and in the UK in January 2026.

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Pancoronavirus vaccine news

There were no new reports or trials in this category this month. I updated the record for the Duke University protein subunit vaccine: The phase 1 trial was fully recruited.

Pancoronavirus vaccine overview

A table below this post keeps track of vaccines I’ve added to this category so far that have publicly available preclinical results. Of these vaccines, 8 have reached phase 1 clinical trials, and 1 has reached phase 2. Some of them have released some results, and they are marked *:

• * CoronaTcP (Gylden Pharma, UK/US) – protein subunit. (Note: This vaccine was previously called PepGNP-SARSCov2, and the manufacturer was previously called Emergex.)

• DIOSynVax (Cambridge University spin-off, UK) – mRNA.
  
  
• Duke University (USA) – protein subunit.
  
  
• INSERM/Ennodc (formerly LinkInVax) (France) – protein subunit.
  
  
• Osivax (France) – protein subunit.
  
  
• SK Bioscience (South Korea) – protein subunit.
  

• * VBI Vaccines (Canada) – eVLP. [This company announced bankruptcy in late 2024.]

• * Walter Reed Army Institute of Research (WRAIR, USA) – protein subunit.

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Addendum 1: List of authorized next generation Covid vaccines (with countries)

There are 7 authorized next-generation Covid vaccines. Only one has been approved by drug regulatory agencies designated stringent, or listed, by WHO – in bold; the others have all been approved in at least one country by a drug regulator WHO has listed with transitional status for vaccines. I’ve listed the vaccines in 2 categories, in order of date of first authorization (or initial approval).

Mucosal:

• Razi-Cov Pars (Iran), intranasal protein subunit vaccine: Iran (October 2021).
• Sputnik (Russia), intranasal viral vector vaccine: Russia (April 2022).
• Convidecia (China), inhaled viral vector vaccine: China (September 2022), Morocco (November 2022), Indonesia (March 2023).
• iNCOVACC (USA/India), intranasal viral vector vaccine: India (September 2022).
• Pneucolin (China), intranasal viral vector vaccine: China (December 2022).

Durable or “variant-proof”:

• Gemcovac (India), self-amplifying mRNA vaccine: India (June 2022).

• Kostaive (LUNAR-COV19) (USA), self-amplifying mRNA vaccine: Japan (November 2023), European Union (February 2025), UK (January 2026).

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Addendum 2: Definitions of vaccine types

• Mucosal vaccines: These enter the body the way the virus does – through mucosal tissues. It’s hoped that provides defence against infection. They can be administered via different routes – squirts or drops in the nose, inhaled through the mouth through a nebulizer (similar to an asthma medication), or in tablet, capsule, or sublingual form.

• Pan-SARS-CoV-2 or “variant-proof” vaccines: These aim to provide protection against any variant of the coronavirus that causes Covid-19.
  

• Pancoronavirus vaccines aim to protect against coronaviruses more broadly – sometimes called “universal coronavirus vaccine.” These vaccines can be targeted to:
  
  – the “subgroup” the 2 SARS viruses came from (the sarbecovirus subgenus),
  
  – coronaviruses from the next level up (the genus, betacoronavirus, which includes MERS as well as the sarbecoviruses), or
  
  – up to the whole coronavirus family, which has 4 genuses, including betacoronavirus and alphacoronavirus (with more common cold viruses).
  
  I classify a vaccine as a pancoronavirus one when the developers are explicitly targeting coronaviruses more broadly than SARS-CoV-2 in the design of the vaccine, and have tested for signs of response to non-SARS-CoV-2 coronavirus(es) (or clearly plan to).

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You can keep up with my work at my newsletter, Living With Evidence. And I’m active on Mastodon: @hildabast@mastodon.online and less so on BlueSky (hildabast.bsky.social).

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Disclosures: My interest in Covid-19 vaccine trials began as a person worried about the virus, as my son was immunocompromised: I have no financial or professional interest in the vaccines. I have worked for an institute of the NIH in the past, but not one working on vaccines. More about me.

The cartoon is my own (CC BY-NC-ND license). (More cartoons at Statistically Funny.)

For details on how I track Covid vaccine progress, see my background post. Notes on my collection of studies are here. The collection is in a public Zotero library you can dig into here.

Previous update posts specifically on next generation Covid vaccines prior to this monthly series (beginning May 2023):

1. Mucosal vaccines (March 2022)
2. Pan-SARS-Cov-2 and pancoronavirus (July 2022)
3. Mucosal vaccines (July 2022)
4. Mucosal vaccines (September 2022)
5. Mucosal vaccines (April 2023)
6. Pancoronavirus vaccines (April 2023)

All my posts on Covid vaccines, beginning from March 2020, are tagged here.

All previous Covid-19 posts at Absolutely Maybe

My posts at The Atlantic and at WIRED.

Postscript: US Project NextGen funded trials

Mucosal vaccines:

• Phase 1 for MPV/S-2P, the intranasal viral vector vaccine developed by the NIH’s National Institute of Allergy and Infectious Diseases (NIAID). This trial for 60 participants began recruiting in July 2024, and finished recruiting by early 2025.

• Phase 2b for the oral viral vector vaccine from Vaxart (trial start announced at the end of September 2024; trial registration here) – further recruitment for this trial was cancelled, though followup will be completed for the participants already dosed (around 5,000). The company has a deal with Dynavax to take the vaccine forward, depending on phase 2 trials.
• Phase 2b for the intranasal viral vector vaccine from CyanVac/Blue Lake Biotech (trial started in December 2024, trial registration here) – no recent news on this trial.

• 2 trials are apparently not going ahead: A Phase 2b (“mini-efficacy”) for the intranasal protein subunit vaccine from Castlevax – this grant was paused and may be terminated. Castlevax has since registered a far smaller phase 2a trial with some similar methodological features. Another for the intranasal live attenuated vaccine from Codagenix had not apparently started.

Durable or “variant-proof” vaccines:

• Phase 1 for STX from Capricor (trial began dosing participants in August 2025). Capricor announced in November 2025 that the trial is ongoing.

• Phase 1 for TNX-1800 from Tonix (aiming for lifelong immunity) (planned to go into clinical trial in 2024 – no recent news);

• Funding was terminated for the Phase 2b (“mini-efficacy”) trial for GeoVax (viral vector vaccine).

Note: Gritstone Bio was originally in line for a phase 2b trial for their self-amplifying mRNA vaccine. However, the company declared bankruptcy and in January 2025, their assets were sold.

Pancoronavirus vaccines – presumed canceled:

• CoronaTcP (Gylden Pharma, UK/US) – protein subunit.
• Unnamed (PopVax, India) – mRNA.

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