The skin has ten times more immune cells than muscle tissue
In Queensland, a small Brisbane biotech called Vaxxas has taken a meaningful step in reimagining how vaccines reach the human body — not through a needle, but through a patch that speaks directly to the skin's own immune intelligence. The company's first human clinical trial, launched in late 2022, tests whether microscopic skin injuries can awaken immune cells more powerfully than conventional injections, a question with particular relevance as COVID variants continue to outpace earlier protections. If the science holds, this moment may mark the beginning of a quieter, more elegant chapter in vaccine delivery — one that took eleven years of preparation and just over a year to move from animal studies to human arms.
- The race to outmaneuver COVID variants has pushed Vaxxas to compress a process that normally takes fifteen years into a single urgent year between pre-clinical results and human trials.
- The central tension is biological: traditional needles bypass the skin's dense population of immune cells, while the patch exploits that concentration through painless micro-injuries — a fundamentally different immunological conversation.
- Preliminary safety and antibody data are expected by late February 2023, with the company watching those numbers closely before committing to a phase two trial targeting people already four doses into conventional vaccination.
- Backing from the Gates Foundation, a pre-market licensing deal with Merck, and over $106 million raised signal that the scientific and commercial worlds are already placing cautious bets on this technology.
- The company is simultaneously scaling its workforce, building a pilot production facility in Brisbane, and recruiting manufacturing leadership — a fragile but deliberate pivot from research lab to market-ready producer.
In Brisbane, an eleven-year-old biotech company called Vaxxas has begun its first human clinical trial for a needle-free COVID-19 vaccine patch — a milestone that its CEO David Hoey describes as unusually swift, arriving just over a year after the publication of pre-clinical results. The phase one trial is focused on two foundational questions: whether the patch is safe, and how effectively it stimulates the immune system. Preliminary answers are expected by late February 2023, with final data to follow by early May.
The science behind the patch rests on a simple anatomical insight that needles overlook. Human skin holds the body's highest concentration of immune cells, and Vaxxas's technology creates microscopic, painless injuries that activate those cells and direct them toward the vaccine antigen. Animal studies have shown this method produces stronger protection against COVID variants than conventional injections — a finding the human trials are now designed to test. The company holds an exclusive license from the University of Texas at Austin to apply this delivery method to a SARS-CoV-2 spike subunit vaccine.
Should phase two proceed by early 2024, it will likely enroll people who have already received four doses of standard COVID vaccines, measuring whether the patch can meaningfully boost immunity in already-primed immune systems. The company has raised more than $106 million in combined equity and grants, counts the Gates Foundation among its supporters, and has already secured a licensing deal with Merck for an undisclosed vaccine — a striking vote of confidence for a product not yet on the market.
Vaxxas now employs 115 people and is moving into a new Hamilton facility to house its first pilot-scale production line. Hoey believes a market-ready vaccine is achievable within four years, though that timeline remains contingent on trial outcomes, regulatory approvals, and the complex work of scaling manufacturing. For now, the company waits — and watches — for February's first numbers.
In Queensland, a small Australian biotech company has begun testing what could become the first needle-free COVID-19 vaccine to reach patients. Vaxxas, an eleven-year-old Brisbane firm, has launched its first human clinical trial for a patch vaccine designed to work differently than the injections most people have already received.
The company's CEO, David Hoey, described the speed of progress as remarkably efficient. From publishing pre-clinical results to opening human trials took just over a year—a compressed timeline in an industry where most vaccines take fifteen years from concept to market. The phase one trial will measure two things: whether the patch is safe, and how well it triggers the body's immune response. Vaxxas expects to have preliminary data by late February, with final results by late April or early May. If those numbers look promising, the company aims to move into phase two testing by early 2024.
The patch works on a principle that needles cannot match. Human skin contains the body's highest concentration of immune cells. Vaxxas's technology creates microscopic injuries in the skin—small enough to be painless—that wake up those immune cells and help them find and respond to the vaccine antigen. Animal studies have shown this approach produces stronger protection against COVID variants than traditional injections do. The company holds an exclusive license from the University of Texas at Austin to use this patch delivery method with a SARS-CoV-2 spike subunit vaccine.
If phase two moves forward, it will likely recruit people who have already received four doses of conventional COVID vaccines. This matters because it tests whether the patch can boost immunity in people whose immune systems have already seen the virus or its vaccine versions multiple times. Hoey said the trial will administer two patch doses and measure how much the antibody response increases, along with other markers of functional immune response.
Vaxxas is not starting from nothing. The company has raised more than $66 million in equity funding and another $40 million in non-dilutive grants, including support from the Bill and Melinda Gates Foundation. Its investors include OneVentures, Brandon Capital, and the US-based HealthCare Ventures. More tellingly, Merck—one of the world's largest vaccine manufacturers—has already signed a deal to use Vaxxas's patch technology for an undisclosed vaccine, even though Vaxxas has not yet brought any patch vaccine to market. The company now employs 115 people and is moving into a new facility in Brisbane's Hamilton suburb that will house its first pilot-scale production line.
Hoey believes the company can have a vaccine available to patients within four years. That timeline assumes the trials succeed and regulators approve the product. He acknowledged that different vaccines in Vaxxas's pipeline face different regulatory pathways, and that manufacturing scale-up requires hiring experienced people—the company recently recruited Scott Fry, formerly of Ellume, as chief operating officer. The transition from research company to revenue-generating manufacturer is underway, but it remains gated by how quickly regulators will allow the trials to progress. For now, the company waits for February's first results.
Citas Notables
Phase one is all about safety, but you're basically measuring the antibody response to the vaccine, so you get a very good idea about the potency of the vaccine and potential efficacy.— David Hoey, Vaxxas CEO
Within four years, the company expected to be shipping its first vaccines.— David Hoey, Vaxxas CEO
La Conversación del Hearth Otra perspectiva de la historia
Why does a patch work better than a needle if they're delivering the same vaccine?
They're not quite the same vaccine. The patch version is formulated differently because it works through the skin's immune system rather than muscle tissue. The skin has ten times more immune cells than muscle, and the micro-injuries activate them locally.
So you're saying the location matters more than the dose?
Exactly. It's about access. When you inject into muscle, the vaccine has to travel to find immune cells. With the patch, the immune cells are already there, waiting.
The article mentions animal studies showing better variant protection. How confident are they in that?
Confident enough that Merck signed on before human trials even started. That's not a small bet. But animal studies and human bodies don't always align, which is why phase one matters.
Four years to market seems fast for a vaccine.
It is, but they're not starting from zero. They have the technology, the funding, the manufacturing partner. What they need now is proof it works in people. If phase two goes well, they could compress timelines further.
What happens if the patch doesn't outperform needles in humans?
Then it becomes a convenience play—easier to administer, no needles, maybe better for needle-phobic patients. But the real value proposition is the variant protection. Without that, it's harder to justify the regulatory and manufacturing complexity.