Our research and development efforts cover a broad spectrum of critical healthcare issues, including cancer, chronic kidney disease, serious infection, malaria, rhabdomyolysis, acute kidney injury. 

1. About PTX-078: PTX is developing two products that treat five different patient populations. PTX-078 is designed to prevent an injury to the kidneys in patients undergoing chemotherapy as well as prevent hearing loss in patients that are receiving a class of antibiotics called aminoglycosides. Although this seems to be a very broad group of patients, they all have a similarity, which is based on a certain cell receptor present in certain organs such as the kidney and inner ear. Although the global market is very large for PTX-078 in adults, it will be particularly useful in the pediatric population, especially those receiving chemotherapy and those suffering from malaria and other infections. 

a. Use of PTX-078 in Patient with Cancer. Cancer patients oftentimes undergo chemotherapy with platinum-based drugs such as cisplatin, which is the most effective, most commonly used, and most toxic chemotherapy agent. Oncologists have major concerns about the loss of hearing and kidney function. They monitor the patient for signs of toxicity, which is the primary cause of decreasing the dose and duration of treatment, and thus potentially decreasing its effectiveness. PTX-078 is designed to prevent nephrotoxicity and ototoxicity in patients undergoing platinum-based chemotherapy and may allow for a higher dose and longer duration of treatment. The market opportunity for PTX-078 is $2.8 billion in the United States and over $5 billion worldwide. 

b. Use of PTX-078 in Patients with a Serious Infection. Patients that develop an infection require an antibiotic. Commonly used antibiotics are aminoglycosides such as gentamicin, amikacin, tobramycin, neomycin, and streptomycin. However, these drugs must be used cautiously due to the risk of hearing loss. Hair cells of the inner ear are essential for hearing function. They don’t regenerate and damage leads to impairment or complete loss of hearing. One common cause of hair cell death is exposure to aminoglycoside antibiotics. As a result, up to 25% of patients treated with AG develop irreversible hearing loss. Patients suffering from recurrent or severe infection are at high risk. Entry of aminoglycosides into hair cells induces cell death, which is thought to be mediated by reactive oxygen species and caspase activation, although caspase-independent cell death can also occur. Nevertheless, access to endolymph requires entry into the inner ear. Although extensive work has characterized the intracellular events occurring after AG entry into hair cells, no clinical studies have measured the efficacy of PTX-078 to prevent entry of ototoxic agents into the inner ear, which may have a protective effect and mitigate hearing loss.

c. Use of PTX-078 in Patients with Severe Malaria. Malaria and sepsis are leading causes of acute kidney injury (AKI) in children in sub-Saharan Africa. Recent estimates suggest that AKI occurs in 24-59% of children with severe malaria. Although the presentation of blackwater fever (BWF) subsided, it recently made a resurgence. Increase recognition of AKI in severe malaria has coincided with increased reports of BWF in African children. Blackwater Fever is a complication of malaria in which red blood cells burst resulting in an accumulation of hemoproteins that overwhelm the capacity of endogenous hemoprotein scavengers (e.g., haptoglobin, hemopexin). The proximal tubular epithelium is the primary route of hemoprotein clearance when endogenous scavenger systems are saturated. Exposure of renal proximal tubular cells to excess cell-free hemoglobin and heme lead to direct cellular injury and AKI through increased oxidative stress, tubulointerstitial inflammation, and endothelial activation. PTX-078 is designed to protect the kidney from BWF. 

2. About PTX-501: Patients on dialysis 3 times per week may experience muscle cramps which are painful and may cause the patient to prematurely discontinue therapy. PTX-501 is designed to prevent muscle cramps in patients undergoing dialysis. PTX is conducting a Phase 1b study in Australia. The market opportunity for our follow-on product, PTX-501, is $454 million.