RDT Research
Rare Disease Therapeutics, Inc. works closely with the FDA’s Office of Orphan Product Development, National Organization for Rare Disorders (NORD), the National Institutes of Health, large international pharmaceutical companies, and patient advocacy groups to identify the unmet needs of patients with rare diseases and identify the potential products to meet these needs.
Recombinant Wolinella Succinogenes Asparaginase
The enzyme L-Asparaginase has been proven to be an effective agent in the treatment of acute lymphoblastic leukemia (ALL), however, patients may develop antibodies to the medication after several treatments resulting in allergic reactions or inactivation of the asparaginase and thus limiting the use of the product.
Recent reports have established that the more intensive use of Asparaginase results in improved survival in ALL patients. Therefore, there is a need for a immunologically distinct asparaginase that can be used even after antibodies have developed to other asparaginase products. Rare Disease Therapeutics, Inc., has licensed such a product in recombinant Wolinella Succinogenes asparaginase from Children’s Hospital of Los Angeles Research Institute and has the product in preclinical development.
Childhood acute lymphoblastic leukemia (also called acute lymphocytic leukemia or ALL) is a disease in which too many underdeveloped infection-fighting white blood cells, called lymphocytes, are found in a child’s blood and bone marrow. In the United States, about 3,000 children each year are found to have acute lymphoblastic leukemia. Peak incidence occurs from 3 to 5 years of age. Before treatment was available, most people who had ALL died within 4 months of the diagnosis. Now, nearly 80% of children and 30 to 40% of adults with ALL are cured. An immunologically distinct asparaginase may benefit those patients failing conventional treatment.
The focus of therapy for ALL is to eradicate all leukemic cells from the marrow and lymph tissue and eliminate any residual foci of disease within the CNS. Treatment is divided into three stages: (1) induction, (2) CNS prophylaxis, and (3) postremission therapy. The number of patients with ALL who enter remission, stay in remission for years, or are cured has increased significantly over the past 30 years. However, the leukemia cells of some patients are not as easily killed by drugs as those of other patients. This may lead to a failure of current treatment and/or relapse. A new asparaginase product may provide yet another chance for treatment and hope for a cure.
F(ab’)2 Antivenoms
Rare Disease Therapeutics, Inc., has entered into a joint development and distribution agreement with Instituto Bioclon, S.A. De C.V., a large , well established Mexican biotechnology company, to develop a series of much needed, high quality antivenoms for the United States and Canada.
Anavip® is a Crotalinae (pit viper) equine immune F(ab’)2 antivenom used in the treatment of envenomation by Crotaline snakes. It contains venom-specific antigen binding fragments derived from equine hyperimmune plasma. These fragments bind to venom thereby preventing or reversing the local and systemic effects of pit viper envenomation.
All vipers native to North America belong to subfamily Crotalinae, also known as the pit vipers. This subfamily includes rattlesnakes, copperheads and cottonmouths in the United States. Pit viper venoms contain a broad variety of toxins, including polypeptide “lethal factors” and “hemorrhagins” that promote capillary leak, proteases, lipases, hyaluronidase, thrombin-like enzymes that promote defibrination, and platelet –aggregating factors.
Clinical consequences of pit viper envenomation included local and systemic injury, both of which may progress for hours or days. Local injury commonly involves edema, erythema, tenderness, ecchymosis, and hemorrhagic bulla formation. Injury always begins as a small region near the fang entry site, but rapid contiguous and lymphatic spread may result in the involvement of an entire limb within a few hours of envenomation. Systemic consequences of crotaline envenomation include shock, coagulopathy, and occasionally, neurotoxicity. Crotaline snake bite still kills 5-19 patients per year in the United States.
Analatro®, Latrodectus immune F(ab’)2 antivenom is used to treat black widow spider envenomations. The genus Latrodectus is found worldwide with several species indigenous to the United States, including those commonly referred to as the black widow spiders.
Black widow spider venom contains several toxic components; the most significant in human envenomation is a potent neurotoxin, alpha-latrotoxin. A black widow spider envenomation can be a life threatening event especially in a young child.
The black widow spider envenomation results in a syndrome that commonly presents with pain at the bite site but with mostly unremarkable local skin findings. However, within 30 to 60 minutes after the envenomation, the neuromuscular symptoms present as involuntary spasm and rigidity progressing proximally from the envenomation site to large muscle groups of the limbs and abdomen. Other clinical symptoms may include fasciculation, hyperactive reflexes, weakness, ptosis, priapism, vomiting, fever, salivation, perspiration, and bronchorrhea, hypertension, increased cerebrospinal fluid pressure and tachycardia early in the course changing to bradycardia late. In addition to the severe muscle pain, patients have described severe headache, anxiety and fatigue.
More information about Instituto Bioclon and the treatment of envenomation by poisonous animals can be found at REDTOX.ORG.