Pfizer executives thought they had a blockbuster waiting after signing a $5.2 billion deal to acquire Anacor Pharmaceuticals and its atopic dermatitis drug candidate. The product gained FDA approval in 2016, but fierce competition prevented it from meeting high expectations. Pfizer has since attempted to monetize other Anacor assets, and one is now in the hands of AN2 Therapeutics. The small molecule is on track for a pivotal test in a rare lung disease, and AN2 plans to fund clinical research by going public.
AN2 filed preliminary IPO documents with securities regulators on Friday evening. The Menlo Park, Calif.-based company has not yet set the size of the transaction or the pricing terms of the proposed stock offering. AN2 has applied to list on Nasdaq under the ticker symbol “ANTX”.
AN2’s research now, and Anacor before it, is based on boron chemistry. The ability of the fifth element of the periodic table to bind to biological targets is a key characteristic that gives it the potential to address targets that have been difficult to address with traditional carbon-based molecules, AN2 said in its d ‘Initial Public Offering. Since boron drugs are selective for their biological targets, the risk of off-target effects is minimized. The element also makes it possible to “adjust” the properties of a drug.
Before crisaborole, the atopic dermatitis drug Anacor (now marketed as “Eucrisa”) which was the key target of Pfizer’s acquisition, the biotech had previously obtained FDA approval for another drug boron based. Tavaborole (marketed by Pfizer as Kerydin) is an antifungal that blocks protein synthesis. AN2’s drug candidate, epetraborole, is a boron-containing analog of tavaborole designed to target protein synthesis in bacteria. AN2’s primary drug target disease is non-tuberculous mycobacterial lung disease (NTM), a rare, chronic and progressive infectious disease. This disease, caused by mycobacteria, leads to irreversible lung damage that can become fatal.
The AN2 drug offers a broad spectrum of activity against mycobacteria, the company said. AN2 is developing the drug, an oral product designed for once-daily use, for the treatment Avian mycobacterium complex lung disease (MAC), which is the most common type of NTM lung disease.
Patients with difficult-to-treat cases of MAC lung disease have an FDA-approved therapy available to them. Insmed got the approval in 2018 for Arikayce, an inhaled formulation of the injectable antibiotic amikacin. But AN2 points out in its IPO filing that clinical trial results showed that Arikayce, combined with gold standard antibiotics, led to resolution of MAC infection in only 29% of patients, leaving many room for other treatment options. The drug Insmed also has tolerance and safety issues which are described in a boxed warning on its label.
“We believe that improved treatment of NTM lung disease will require an effective, safe and well-tolerated antibiotic with a novel mechanism of action that is unaffected by resistance to existing antibiotics and has a convenient oral dose, once a day,” AN2 said in the IPO filing.
AN2 is led by President and CEO Eric Easom, former Anacor Vice President for Neglected Diseases. According to the biotech prospectus, the company was established in 2017 and officially launched in 2019 backed by a $12 million Series A funding round. Around this time, AN2 also unveiled a partnership with Brii Biosciences, which licensed the rights to develop the biotech’s leading antibacterial program in China. AN2 closed a Series B financing of $80 million round last year. The company’s largest shareholder is Adjuvant Global Health Technology Fund, which owns 17.2% of biotech, followed by RA Capital Management’s 14.2% stake, according to the prospectus.
At the end of last year, AN2 said its cash position was $62 million. Combined with proceeds from the IPO, the company plans to deploy its cash towards the clinical development of epetraborole in an ongoing Phase 1 study in renal failure and the clinical trial of phase 2/3 planned. The company said the pivotal study is expected to begin in the first half of this year; preliminary phase 2 data are expected in mid-2023. AN2 also plans to use some of the money to develop its lead drug for other geographic markets, with an initial focus on Japan, as well as developing the molecule for other pulmonary indications.
The timing of AN2’s IPO, or any stock offering, is uncertain. Financial markets were already rocked by worries about inflation and equity volatility. Now, any company planning to sell stock must also consider Russia’s invasion of Ukraine and the effects the conflict will have globally, wrote Bill Smith, the company’s co-founder and CEO. IPO researcher Renaissance Capital, in its weekly IPO update.
“Fear and uncertainty over the war in Ukraine overshadowed a strong US jobs report, and growth stocks took a hit,” Smith said. “This means the IPO window will remain closed. Any investor looking to buy would rather grab their favorite IPOs when they are 50% off recent highs than spend time hunting for new deals.
London-listed Okyo Pharma files for U.S. IPO
Okyo Pharma deposit paperwork with the US securities regulator for an initial public offering of US depositary shares. U.K.-based Okyo has been listed on the London Stock Exchange under the ticker symbol “OKYO” since 2018. The biotech did not specify how many shares it plans to offer in its stock offering to United States, and no pricing details were disclosed. Okyo applied to be listed on Nasdaq under the same ticker symbol as its London listing.
Okyo aims to treat eye disorders by targeting G-protein-coupled receptors (GPCRs), membrane receptors found throughout the body that are essential for various biological functions. Okyo’s lead therapeutic candidate, OK-101, is a peptide drug designed to target chemokine-like receptor 1, a GPCR important in the development of inflammatory eye disease. This GPCR target can be activated and modulated by chemerin, a protein present in the body. But the chemerine has a short half-life. OK-101 is a chemerin analogue designed to be more stable. Okyo’s drug candidates are based on technology licensed from On Target Therapeutics.
The main disease targeted by OK-101 is dry eye. Okyo said in the IPO documents that OK-101 also has potential application in treating nerve pain in the eye, eye inflammation and allergic conjunctivitis. In the prospectus, Okyo said it plans to use the money from its U.S. IPO to advance OK-101 toward filing an investigational new drug application and clinical development in dry eye disease. This application is expected to be filed with the FDA in the third or fourth quarter of this year, the filing says.
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