After nearly a decade of delays Allergy Therapeutics (OTC:AGYTF) is getting back on track with its short-course allergy vaccines. The company expects results from two phase II studies at the end of June: one in the US with Pollinex Quattro Grass, the other in Europe with Pollinex Quattro Birch.
The UK group hopes that the grass vaccine will be the first seasonal subcutaneous immunotherapy to reach the US, with phase III trials to start later this year and launch in 2020 if all goes well. In Europe, Allergy already sells its Pollinex Quattro products on a named-patient basis, with revenues of £43m ($60m) in 2015, but is also seeking its first formal approval.
The US opportunity is “potentially transformational”, say Edison analysts, who put peak US sales for the Pollinex Quattro range – including the grass vaccine, the tree vaccine and a third product, Pollinex Quattro Ragweed – at $1.1bn.
This would be quite a turnaround from 2007, when Allergy was forced to delay its research program after an adverse event. Although this turned out to be unrelated to the vaccine, the FDA did not lift its clinical hold until 2012 after it had conducted a review of novel vaccine adjuvants.
Subcutaneous vs sublingual
Allergy did not resume US clinical development until last year. In the meantime, the company’s vaccines have been overtaken by sublingual allergy treatments developed by Stallergenes and ALK Abello.
But these oral treatments have not taken off, perhaps owing to a preference for subcutaneous vaccines in the US. Allergy's chief executive, Manuel Llobet, tells EP Vantage that, being subcutaneous, Pollinex Quattro “will have a really fast penetration”.
Somewhat counterintuitively, he believes that compliance with Allergy’s vaccines, which require four to six injections, is better than with sublingual treatments. “You might have to go to the doctor six times, but then that’s it. With the tablet you have to take one every day for at least a year, and patients don’t really follow the treatment.”
Allergy’s products should also be preferable to the “homebrew” vaccines currently used in the US, which require 50-100 injections and do not necessarily adhere to good manufacturing practices, he adds.
However, first Allergy needs to succeed in phase II, which might be easier said than done. A UK rival, Circassia (OTC:CSSPF), tripped up in a phase IIb trial of its ragweed allergy vaccine (Circassia falls victim to placebo effect, December 8, 2014).
Mr. Llobet is upbeat about Allergy’s chances. The group has chosen to take different products forward in the US and Europe as a way of “optimizing the clinical work”, he explains. For example, the US study of the grass vaccine is designed to find the optimum dose, and “we’ll probably use the same dose in Europe”.
There is a chance that the upcoming phase III programs could be unified to include patients in both the US and Europe, supporting approval in both territories, but there are pros and cons to this approach.
“It has some downsides, like coordinating different regulatory authorities, and time is precious here,” says Mr. Llobet. “So maybe it’s better to just go ahead and do it faster, then repeat with another phase III study including European centers [for Pollinex Quattro Grass].”
The tree vaccine could be launched in the US by 2022, while Pollinex Quattro Ragweed could be available by 2023, say the Edison analysts.
Mites and peanuts
Allergy is already looking beyond Pollinex Quattro to earlier-stage projects that are perennial, rather than seasonal, including its Acarovac Quattro dust mite vaccine, which is to start phase I development this year.
Then there is its Polyvac Peanut vaccine, based on virus-like particle (VLP) technology licensed from Saiba Biotech, which could go into phase I in a year or two, Mr. Llobet estimates.
As with Allergy's other subcutaneous vaccines, he is convinced that Polyvac Peanut will have an edge over rival peanut allergy therapies in terms of compliance, including Aimmune Therapeutics’ (NASDAQ:AIMT) oral candidate AR101 and DBV Technologies’ (NASDAQ:DBVT) Viaskin Peanut patch, both in phase III.
Many potential users are children, who might not remember to take a pill every day or for whom a patch might not be ideal. “I have two kids and they’re running around all day and changing their clothes 10 times a day. I don’t know [if a patch would work],” the chief executive says
Allergy, which raised £31.5m last year in two fund raisings, should have enough cash to take its Pollinex Quattro range to market, Mr. Llobet believes, but might need to raise more to complete development of its earlier-stage candidates.
As for commercializing its vaccines in the US, “we’ll decide in 2017 if we go it alone or we go with a partner”. Of course, these discussions will hinge on whether it succeed in phase II.