We have two more survivors of rabies associated with use of the MP. Survival in rabies is nominally 8%, based on an intention-to-treat analysis of all known attempts at the MP (n = 25). Under MP version 2 (n = 10), in which ribavirin is avoided and prophylaxis against vasospasm is suggested, survival is estimated to be 20%. Intention-to-treat analyses avoid many biases in clinical trials and better estimate effectiveness in the real world, which is why this conservative approach has been chosen for our statistics. Our registry includes patients with demise within hours, protocol deviations and conditions that conflict with the hypotheses underlying the MP. (The hypotheses are that the patient's condition is reversible and that the patient will have a natural immune response.) The registry includes, for example, three immunosuppressed patients who received rabies through transplanted organs.
While rabies used to be 100% lethal and we now have at least 8% survival, these are still poor odds, and there is considerable economic cost to intensive care over several weeks. This poses the question: should we persist? Survival for acute lymphocytic leukemia was still poor after a decade of early attempts, and a vigorous debate in the medical literature at that time addressed the 'futility' of cancer care. A total of 30 years later, survival from childhood acute lymphocytic leukemia exceeds 80% using the very same classes of drugs that are used more wisely, with more experience and with a better understanding of the fundamental biology. Our understanding of the fundamental biology behind the MP should rapidly improve because the National Institute for Allergy and Infectious Diseases (NIAID) recently contracted the development of a ferret model for the treatment of rabies, under N Bourne at University of Texas Medical Branch, Galveston, TX, USA.
Future Virology. 2009;4(6):563-570. © 2009 Future Medicine Ltd.
Cite this: Are We Getting Closer to the Treatment of Rabies? - Medscape - Nov 01, 2009.