Boric acid

RESEARCH TRIANGLE PARK, N.C., Feb. 01, 2024 (GLOBE NEWSWIRE) -- Fennec Pharmaceuticals Inc. (NASDAQ: FENC; TSX: FRX), a commercial stage specialty pharmaceutical company, today announced that the U.S. Food and Drug Administration (FDA) has issued a public reminder to healthcare providers that PEDMARK (sodium thiosulfate injection) is not substitutable with other sodium thiosulfate products as explicitly directed in its prescribing label. PEDMARK is the first and only FDA approved therapy indicated to reduce the risk of ototoxicity (e.g., permanent hearing loss) associated with cisplatin in pediatric patients 1 month of age and older with localized, non-metastatic solid tumors. The FDA stated in the public communication that it is aware that some providers may be preparing other sodium thiosulfate (STS) products for patient use in place of PEDMARK, including diluting STS products approved for other uses to match the strength of PEDMARK. The FDA reminded health care providers that as stated in PEDMARK’s prescribing information, PEDMARK is not substitutable with other sodium thiosulfate products. The FDA stated that such substitutions pose potential health risks, including: Potassium chloride exposure which, at high doses, can lead to increased risk of acute cardiac events and other serious adverse reactions. Potassium chloride is not present in PEDMARK. Overexposure to boric acid (a boron compound), can cause health risks including headache, hypothermia, restlessness, weariness, renal injury, dermatitis, alopecia, anorexia and indigestion. Although PEDMARK also contains boric acid, it is at a lower concentration than other STS products. Overexposure to sodium nitrite, which can lead to health risks including methemoglobinemia. Sodium nitrite is co-packaged with sodium thiosulfate as a separate vial in some products; it is not present in PEDMARK. The public communication was issued by the FDA’s Professional Affairs and Stakeholder Engagement Staff within the Center for Drug Evaluation and Research, Office of Communications. The FDA encourages those with any questions to contact FDAOncology@fda.hhs.gov. About Fennec Pharmaceuticals Fennec Pharmaceuticals Inc. is a specialty pharmaceutical company focused on the development and commercialization of PEDMARK® and Pedmarqsi to reduce the risk of platinum-induced ototoxicity in pediatric patients. Further, PEDMARK received FDA approval in September 2022 and European Commission Marketing Authorization in June 2023 for Pedmarqsi. PEDMARK has received Orphan Drug Exclusivity in the U.S. for seven years of market protection and Pedmarqsi has received Pediatric Use Marketing Authorization in Europe which includes eight years plus two years of data and market protection. Fennec has a license agreement with Oregon Health and Science University (OHSU) for exclusive worldwide license rights to intellectual property directed to sodium thiosulfate and its use for chemoprotection, including the reduction of risk of ototoxicity induced by platinum chemotherapy, in humans. For more information, please visit . Investors: Robert Andrade Chief Financial Officer Fennec Pharmaceuticals Inc. +1 919-246-5299 Corporate and Media: Lindsay Rocco Elixir Health Public Relations +1 862-596-1304 lrocco@elixirhealthpr.com

Aquaporins, which move water through membranes of plant cells, were not thought to be able to permeate sugar molecules, but researchers have observed sucrose transport in plant aquaporins for the first time, challenging this theory. Aquaporins, which move water through membranes of plant cells, were not thought to be able to permeate sugar molecules, but University of Adelaide researchers have observed sucrose transport in plant aquaporins for the first time, challenging this theory. The finding, made by researchers from the School of Agriculture, Food and Wine, widens the concept of aquaporins' role in plant biology and will have implications for the bioengineering of plants for food production and plant survival. Aquaporins, which belong to a class of membrane proteins known as water-transporters, were first identified in 1993 by American molecular biologist and Nobel Laureate, Peter Agre. The concept of water-permeation in small molecules was accepted at the time, but it was unclear if aquaporins could permeate larger molecules, such as sucrose. This has now been demonstrated, with researchers employing a multidisciplinary approach to observe the biochemical process in HvNIP2;1, which is a Nodulin 26-like Intrinsic Protein found in barley. "We used nanobiotechnology, electrophysiology, protein chemistry, protein modelling and computational chemistry. We also integrated vast experimental and theoretical data with phylogenomics exploring around 3,000 aquaporins," said the University of Adelaide's Professor Maria Hrmova. HvNIP2;1 is different from other sub-clades of aquaporins in that it has altered structural characteristics and thus it acquired the ability to transport saccharides. Researchers are interested to see what other functions it may serve and how this relates to in planta function. "We also performed full-scale steered molecular dynamics simulations of HvNIP2;1 and a spinach aquaporin -- a structurally and functionally divergent aquaporin compared to HvNIP2;1 -- revealing potential rectification of water, boric acid, and sucrose. This will be the subject of future studies," said Professor Hrmova. The discovery has been published in the Journal of Biological Chemistry, a forum for fundamental research at the intersection of biochemistry, biophysics and biology, and demonstrates the importance of questioning assumed knowledge. "This work exemplifies that we need to be more open-minded about what different aquaporins may permeate, besides water," said the paper's co-author, Professor Steve Tyerman, who previously revealed ion permeation in plant aquaporins. "Water may be secondary to other important molecules in aquaporins, or some may be co-transport water and other molecules by virtue of a vast array of protein-ligand interactions," said Professor Hrmova. Understanding the properties of aquaporins is important for bioengineering to design novel proteins with improved characteristics, such as substrate specificity, thermostability, and folding. These properties are fundamental to the survival of plants as they mediate water and nutrient uptake, govern the distribution of solutes through plants, remove toxins from the cytosol, and recycle valuable sugars. Given their gatekeeping functions, aquaporins and other membrane transporters are attractive targets in agricultural biotechnology for increasing nutrient contents in edible parts of crop plants, excluding toxic elements, which together directly affect crop quality and ultimately sustained production of our food.