The paper, ‘A case of progressive multifocal leukoencephalopathy and idiopathic CD4+ lymphocytopenia,’ published in the Journal of Antimicrobial Chemotherapy, provides an overview of the treatment of a single adult patient with PML, a rare and usually fatal disease caused by the human polyomavirus JC.
Recombinant human interleukin-7 (CYT107) is a critical immune-modulator for immune T-cell recovery and enhancement.
Under development by Chimerix, CMX001 is in Phase 2 clinical studies in immunocompromised transplant and cancer patients for the treatment of life-threatening viruses, including cytomegalovirus and adenovirus.
The combination therapy succeeded in eradicating the polyomavirus JC, the virus that causes PML in less than two weeks following initiation of CYT107 treatment, and four weeks following the introduction of CMX001.
Cytheris DVM, president and CEO Michel Morre said the combination of CYT107 with a powerful antiviral agent to treat PML follows the same therapeutic regimen that Cytheris is investigating in clinical studies of HCV and HBV, where interferon or antiviral therapy is employed to drop the viral load and is then followed by added treatment with CYT107 to clear the virus, a process accompanied by an increase in CD4 and CD8 T cell counts
"In responding patients, comparison of the resulting trend lines in decreased viral load and increased CD4 count over time shows an almost identical pattern when the PML case described in Dr Patel’s report is compared to CYT107-treated patients who have cleared the HCV virus. We believe the same pattern will soon emerge as we reach the higher dose range in our HBV CONVERT study, currently being conducted in France and Italy," Morre said.
Dr Patel said though both experiential and experimental data in the treatment of PML have grown quite considerably in recent years, it is important to keep in mind that there still are no known interventions that can reliably prevent or adequately treat PML.
"To my knowledge, this is the first case report to demonstrate the use of combination therapy, in this instance two investigational medications, as a possible therapeutic strategy for the treatment of PML," Dr Patel said.
Cytheris, which operates from its headquarters and laboratories in Issy-les-Moulineaux, a suburb of Paris, and its US subsidiary in Rockville, Maryland, is a privately held clinical-stage biopharmaceutical company focused on research and development of new therapies for immune modulation.