Prurisol™ is Cellceutix’s anti-psoriasis drug candidate. It is a small molecule (MW=344) that acts through immune modulation and PRINS reduction. Prurisol has been found to be effective against psoriasis in animal models, both in induced psoriasis as well as a xenograft model with human psoriatic tissue. Prurisol is synthesized through a five-step process using commercially available starting materials. A patent application covering Prurisol was filed in January of 2012 and is pending.
Cellceutix is developing Prurisol under FDA guidance that a 505(b)(2) designation is an appropriate development pathway. The initial clinical research will be a brief Bio-equivalence crossover study expected to last approximately 45 days with the primary endpoint of demonstration that Prurisol converts to abacavir in humans, as it has been shown to do in animal models. Upon successful completion of the crossover trial, the Company will initiate a larger Phase 2/3 clinical trial under a 505(b)(2) designation, which would permit Prurisol to move to advanced trials because the active moiety of Prurisol is that of a drug already approved by the FDA.
Cellceutix Anti-Psoriasis Drug Prurisol Meets Primary Endpoint of Clinical Trial
BEVERLY, MA–(Marketwired – Aug 7, 2014) – Cellceutix Corporation (OTCQB: CTIX) (the “Company”), a clinical stage biopharmaceutical company developing innovative therapies in oncology, dermatology, and antibiotic applications, is pleased to announce that it has just received notice that the data from its Phase 1 trial of the Company’s anti-psoriasis drug candidate Prurisol™ for the conversion of Prurisol to abacavir indicated “the areas are within passing Bioequivalency limits.” Cellceutix believes it has met the primary endpoints and objectives of the study. Cellceutix is developing Prurisol™ under guidance from the U.S. Food and Drug Administration that a 505(b)(2) designation is an acceptable pathway to expedite development of the compound for treating psoriasis.
Cellceutix: Prurisol(TM) for Psoriasis — FDA Agrees That Phase 2 Study May Begin
BEVERLY, MA–(Marketwired – Dec 10, 2014) – Cellceutix Corporation (OTCQB: CTIX) (the “Company”), a clinical stage biopharmaceutical company developing innovative therapies with oncology, dermatology, and antimicrobial applications, is pleased to announce that the US Food and Drug Administration (FDA) has agreed that Cellceutix may begin a Phase 2 study of Prurisol (abacavir acetate), a potential chronic oral therapy for the treatment of placque psoriasis. Cellceutix conducted a Phase 1 study which demonstrated that the bioavailability of the active component of Prurisol (abacavir) was the same or lower than that of the marketed drug Ziagen® (abacavir sulfate). FDA noted at the end-of-Phase 1 meeting on December 8, 2014 that, pending the full review of the Phase 1 data, long-term safety data for Prurisol in the treatment of psoriasis would not be required.
Prurisol will be eligible for the 505(b)(2) drug approval pathway for the treatment of psoriasis. A potential application to market Prurisol will contain safety and efficacy data from studies conducted by Cellceutix, but at least some of the information required for approval may come from studies not conducted by Cellceutix. In this case, the long term safety data for Ziagen, marketed for over 15 years in the US, will be referenced.
Prurisol Labratory Summary
Prurisol is more effective than conventional therapies in human psoriatic tissue xenografts
» Prurisol (10 mg/kg PO twice/ day x 21 days)
» 84% reduction in lesion appearance
» 99% reduction in lesions based on histology
» 96% reduction in serum PRINS
» 87% reduction in serum IL-20
» No reoccurrence of lesions within 180 days
» Methotrexate (7.5 mg/kg IP once/ day x 5 days)
» 63% reduction in lesion appearance
» 76% reduction in lesions based on histology
» 48% reduction in serum PRINS
» 46% reduction in serum IL-20
» Lesions reoccurred in 61 days
Prurisol is a small molecule, acting on the principles of immune modulation and PRINS reduction that has been found to be effective against psoriasis in animal models, both in induced psoriasis as well as a xenograft model with human psoriatic tissue.
Prurisol was studied in mice that were irradiated with 350 Rads whole body to suppress graft rejection, and then engrafted with human psoriatic tissue by inserting human psoriatic tissue under the skin using a trocar. Groups of ten mice were treated with Prurisol orally for 21 days with either 10 mg/kg Prurisol once/ day or 10 mg/kg Prurisol twice/day, or with 7.5 mg/kg methotrexate IP once/day, or untreated mice as controls. The mice were followed for 180 days. Endpoints were skin appearance, based on a score of 0 for normal appearance to 10 for severe lesion, histological observations, also based on a score of 0 for normal appearance to 10 for severe lesion, PRINS RNA in psoriatic lesions, and blood IL-20 levels. For these parameters, Prurisol was compared to controls and methotrexate.
In a second experiment, groups of 10 immunocompetent CD-1 mice were treated with one or two doses of 10 mg/kg Prurisol daily or 3 mg/kg efalizumab SC once per week for 3 weeks. CD4+ and CD8+ lymphocyte counts were also measured by flow cytometry and compared to efalizumab. Prurisol significantly reduced all psoriatic endpoints measured relative to controls
In addition, psoriasis did not recur during the study period with the higher dose of Prurisol whereas with methotrexate, psoriasis recurred after an average of 61 days. Treatment with Prurisol caused less reduction in CD4+ lymphocyte counts than did efalizumab. Weight loss in the treated animals was within acceptable limits.
Prurisol given at 10 mg/kg twice/day was shown to be more effective than methotrexate in reducing psoriatic skin lesions in a human xenograft model. In addition, Prurisol can be given orally and is well-tolerated.
A variation of Prurisol in human xenograft model. The top row animals show a relatively clean coat with limited discernibility of psoriasis. The bottom row are the untreated control animals.
By SAR, the lead candidate Prurisol is selected. Prurisol in human xenograft model. The top row animals show a clean coat with no evidence of psoriasis, essentially showing that Prurisol cured the psoriasis in the mice. The bottom row shows the untreated control animals.