Adaptive Phage Therapeutics Announces FDA Clearance of IND Application for PhageBank™ in Treatment of Diabetic Foot Osteomyelitis

Adaptive Phage Therapeutics (APT), a clinical-stage biotechnology company dedicated to advancing therapies that address the global rise of multi-drug resistant infections, announced today that the U.S. Food and Drug Administration (FDA) has accepted its Investigational New Drug (IND) application for PhageBank™ phage therapy for the treatment of Diabetic Foot Osteomyelitis (DFO).

“Advancing PhageBank therapy targeting diabetic foot osteomyelitis is a critical step in providing viable treatment options to diabetic patients facing significant morbidities, including potential amputation”Tweet this

“Advancing PhageBank therapy targeting diabetic foot osteomyelitis is a critical step in providing viable treatment options to diabetic patients facing significant morbidities, including potential amputation,” said Greg Merril, CEO and co-founder of Adaptive Phage Therapeutics. “Today’s announcement marks the third successful IND application by APT in the last year, further validating the potential of our novel PhageBank™ platform to more effectively treat a range of drug-resistant bacterial infections and enabling APT to rapidly progress towards multiple clinical inflection points.”

DFO is the result of soft tissue infections in diabetic patients that spread into bone. Based on research by The Center for Biosimilars, someone is diagnosed with diabetes every 17 seconds, and 230 people with diabetes will suffer an amputation every day in the United States. Globally, it is estimated that a leg is amputated every 30 seconds, with 85% of these amputations resulting from a diabetic foot ulcer(1). With more than 1.5 million patients worldwide being diagnosed with diabetes each year, amputations as a result of diabetes comprise a significant portion of non-trauma related amputations. The American Diabetes Association estimates that 20% of patients with diabetic foot infections, and more than 60% of those with severe infections, have underlying osteomyelitis, placing patients at significantly higher risk of amputation(2).

APT’s PhageBank™ is a precision-matched phage therapy that specifically targets bacterial pathogen(s) identified as the cause of patient infection. PhageBank™ comprises a library of purified phages covering a broad spectrum of bacterial species. APT has also developed a proprietary PhageBank Susceptibility Test™ (PST) to rapidly identify the specific phage(s) required to provide precision therapy of bacterial infections.

The Defense Health Agency, a branch of the Department of Defense (DoD), is an integrated Combat Support Agency that enables the military’s medical services to provide a ready medical force in any situation. In 2019 the DoD awarded APT a $14 million contract for advanced development of its PhageBank™ platform. The award is funded by the Defense Health Agency and the Naval Medical Research Center.

APT is advancing clinical trials for all three initial PhageBank™ target indications: in Diabetic Foot Osteomyelitis (DFO), Prosthetic Joint Infections (PJI), and Urinary Tract Infections (UTI). APT’s Phase I/II PhageBank™ DFO trial is planned as a randomized, open-label, parallel-group, controlled study to evaluate the safety and efficacy of PhageBank™ therapy in conjunction with standard of care versus standard of care. APT plans to initiate the DFO clinical trial in 2021, with a first interim data analysis expected in 2022.

1)https://www.ajmc.com/view/increasing-awareness-this-national-diabetes-month-can-save-limbs-and-lives
2)https://www.ncbi.nlm.nih.gov/books/NBK554227/

Adaptive Phage Therapeutics, Inc.

Adaptive Phage Therapeutics (APT) is a clinical-stage company advancing therapies addressing multi-drug resistant infections. Prior antimicrobial therapeutic approaches have been “fixed,” while pathogens continue to evolve resistance to each of those therapeutics, causing those drug products to become rapidly less effective in commercial use as antimicrobial resistance (AMR) increases over time. APT’s PhageBank™ approach leverages an ever-expanding library of bacteriophage (phage) that collectively provide evergreen broad spectrum and polymicrobial coverage. PhageBank™ phages are matched through a proprietary phage susceptibility assay that APT has teamed with Mayo Clinic Laboratories to commercialize on a global scale. APT’s technology was originally developed by the biodefense program of U.S. Department of Defense. APT acquired the world-wide exclusive commercial rights in 2017. Under FDA emergency Investigational New Drug allowance, APT has provided investigational PhageBank™ therapy to treat more than 40 critically ill patients in which standard-of-care antibiotics had failed.

Early treatment for leg ulcers leads to better outcomes for patients

Media Release:

Venous leg ulcers are common and distressing, affecting around 1 in 300 adults in the UK. They are open, often painful, sores on the leg that take months to heal and can develop after a minor injury. People with enlarged veins known as varicose veins are at high risk of developing venous leg ulcers, as they have persistently high pressure in the veins leading to skin damage.

In a clinical trial, led by researchers at Imperial College London and clinicians at Imperial College Healthcare NHS Trust, 450 patients with venous leg ulcers were treated with early surgical interventions. This resulted in faster healing and a reduced risk of the condition coming back compared with current methods of treating patients with compression stockings and delayed surgical interventions.

The researchers behind the study, published in JAMA Surgery, suggest that current guidelines on treating leg ulcers should be revised to include early assessment of varicose veins and surgical treatment of leg ulcers to deliver clinical benefits and cost savings for the NHS. They suggest that this early treatment intervention could save the NHS an estimated £100 million per year.

Lead author of the study Professor Alun Davies, Professor of Vascular Surgery at Imperial College London and a Consultant Surgeon at Imperial College Healthcare NHS Trust, said:

“Venous leg ulcers cause enormous physical and mental distress to patients as well as having a financial impact on the NHS. Our study is the first to show that early surgical treatment of leg ulcers leads to faster healing and the reduced risk of the ulcer coming back compared to current methods.

The NHS spends around 2 per cent of its budget on managing lower limb wounds and there is an urgent need to find more effective treatments. We believe that the current guidelines should be changed so that patients with leg ulcers are treated with surgery at an earlier stage. This approach will lead to better outcomes and improve patients’ quality of life.”

The main treatment for leg ulcers is compression bandages or stockings, to improve the vein function in the legs. There are also surgical treatments such as endovenous ablation – a ‘keyhole’ treatment to close varicose veins. The treatment, under local or general anaesthetic, involves a small fibre passed through a catheter and positioned at the top of the varicose vein. The fibre delivers bursts of energy that heat up the vein and seal it closed. However, under current guidelines this treatment is not usually offered until the ulcer has been present for many months, if at all. Furthermore, if the underlying cause of the ulcer is not treated there’s a high risk of the ulcer coming back after treatment.

The researchers wanted to see whether performing endovenous ablation to treat varicose veins at an earlier stage can lead to faster healing and reduce the risk of venous leg ulcers returning, requiring further treatment.

Researchers recruited 450 patients with venous leg ulcers from October 2013 to September 2016. All patients had leg ulcers of less than six months old and were treated at 20 hospitals in the UK, including Imperial College Healthcare NHS Trust hospitals. Two hundred and twenty four patients were randomly assigned to receive endovenous ablation within two weeks of randomisation followed by wearing compression stockings. The rest of the patients were given compression stockings but the endovenous ablation treatment was delayed by six months or until the ulcer was healed. The researchers then followed up over a period of five years to compare how quickly they healed and the rate of leg ulcer recurrence after treatment.

Of the 426 participants whose leg ulcer had healed, 121 participants experienced at least one recurrence during follow-up. In the early-intervention group, 56 patients experienced recurrence during follow-up. In comparison, 65 participants in the delayed intervention group experience recurrence during follow-up. The rate of recurrent ulcers was 60 per cent higher in the deferred intervention group (0.16 per year of follow-up compared to 0.1 per year in the early-intervention group). They also found that healing was shorter in the early intervention compared to the deferred intervention group.

The team compared the cost of early surgical intervention with delayed intervention over three years and found that early intervention was, on average, the less costly strategy over three years.

A new approach to understanding the biology of wound healing

Press Release:

PHILADELPHIA – Our bodies frequently heal wounds, like a cut or a scrape, on their own. However patients with diabetes, vascular disease, and skin disorders, sometimes have difficulty healing. This can lead to chronic wounds, which can severely impact quality of life. The management of chronic wounds is a major cost to healthcare systems, with the U.S alone spending an estimated 10-20 billion dollars per year. Still, we know very little about why some wounds become chronic, making it hard to develop effective therapeutics to promote healing. New research from Jefferson describes a novel way to sample the cells found at wounds – using discarded wound dressings. This non-invasive approach opens a window into the cellular composition of wounds, and an opportunity to identify characteristics of wounds likely to heal versus those that become chronic, as well as inform the development of targeted therapies.

The study was published in Scientific Reports on September 15th.

“Studying wound healing in humans is very challenging, and we know very little about the process in humans,” says Andrew South, PhD, Associate Professor in the Department of Dermatology and Cutaneous Biology and one of the lead authors of the study. “What we do know is from animal studies, and animal skin and the way it heals is very different from human skin.”

Dr. South and his lab study a group of inherited skin diseases called epidermolysis bullosa (EB), where wound healing is severely impaired. Patients, often from birth, suffer from blisters and lesions that are slow to heal, and some become chronic. In a subset of patients, chronic wounds are at high risk of developing into aggressive skin cancer. At this time, it is very difficult to predict which wounds in a given patient will heal, and which won’t. Being able to sample the wounds is a key to understanding the mechanisms behind healing.

“Performing a biopsy to sample the cells in the wound would help us understand the differences between these wounds,” says Dr. South “But biopsy in these patients is extremely painful and could delay healing of the wound even further. On the other hand, collecting these bandages that are just going to be thrown away, it poses no harm to the patient, and can be applied to a variety of conditions where wounds don’t heal properly.”

The researchers, which included collaborators in Chile and Austria, collected and analyzed 133 discarded wound dressings from 51 EB patients. Both acute and chronic wounds were sampled, with acute defined as present for 21 days or less, and chronic as present for more than 3 months.

“Previous studies had used wound dressings or bandages to collect fluid and look at what proteins are in there,” says Dr. South. “But no one has actually looked at what cells are present. Applying the techniques our lab frequently uses, we were able to isolate viable or living cells from the dressings.”

The researchers recovered a large number of cells from the dressings, often in excess of a 100 million. The larger the wound, and the more time a dressing was on a wound, the more number of cells were recovered.

The researchers then characterized the cells to see what type of cells are present at the wound. They detected a variety of immune cells including lymphocytes, granulocytes or neutrophils, and monocytes or macrophages. When comparing dressings from acute and chronic wounds, they found a significantly higher number of neutrophils at chronic wound sites. Neutrophils are the first line of defense in our immune system, and when a wound starts to form, they’re the first ones to arrive at the scene.

“Previous findings from animal studies and protein analysis of human wound dressings had supported the idea that when neutrophils hang around longer than they should, that stalls the healing process and can lead to chronicity,” says Dr. South. “Our findings support that theory more definitively, by showing that chronic wounds are characterized by higher levels of neutrophils.”

These findings give more insight into wound healing, and could help develop therapies that promote the process; for instance, those that neutralize excess neutrophils, or recruit macrophages, the immune cells that begin the next stage in healing after neutrophils.

The researchers now plan to expand on their technique, by further analyzing the individual cells collected from the wound dressings, and the genetic material inside them. “Currently we’re working with colleagues in Santiago, Chile on collecting dressings from EB patients over a period of time,” says Dr. South. “This allows us to follow patients longitudinally, and observe a wound and how its cellular composition changes as it heals or doesn’t heal.”

The team hopes that this will reveal genetic markers that can predict healing or chronicity.

“This method of sampling could be an alternative to bothersome swabs or blood draws, which are especially hard to do in newborns,” says Dr. South. “Since we know EB can present at birth, this technique could give us really early insight into the how severe the disease might be.”

While the current study focuses on EB, Dr. South and his colleagues hope that this technique can be applied to a variety of other conditions, such as diabetic foot ulcers and vascular leg ulcers.

“The field of wound healing has been crying out for a better understanding of what drives a chronic wound,” says Dr. South. “This technique could be transformative, and eventually help patients live more comfortable and healthy lives.”