A new study shows that Valacyclovir significantly helps a subset of chronic fatigue syndrome patients who test positive for Epstein-Barr virus.
The September/October edition of the journal In Vivo reports on work carried out by researchers at William Beaumont Hospital in Michigan, USA. The research was undertaken to investigate whether valacyclovir would be beneficial in CFS patients who have positive titers for Epstein-Barr virus (EBV).
Valacyclovir (trade name Valtrex®) is a chemical cousin of acyclovir (Zovirax®) and is in fact rapidly converted into acyclovir in the body. These drugs have antiviral actions and are used in the treatment of cold sores and other conditions that are caused by herpes simplex viruses.
The study design involved two parts. First a blinded placebo-controlled trial was conducted in which one group of EBV positive CFS patients received treatment with valacyclovir at a dosage of 14.3mg/kg every six hours while another group of patients received a placebo, again every six hours. This part of the study lasted for six months in total.
The second part of the study involved following the progress of the participants up to thirty-six months from the start of the trial.
To assess the progress of the study participants the researchers used a combination of immunological tests and questionnaires. The immunological tests included measuring levels of antibodies to EBV as well as the antigens produced by the virus itself. In this way the researchers could determine both the activity of the virus as well as the immune response towards it. A point score system known as the Energy Index (EI) was given to all participants regularly to assess physical functioning capacity, i.e. their energy levels and ability to function.
The research team reported that after six-months patients receiving valacyclovir experienced an increased EI point score of +1.12 units which is equivalent to an extra 122 calories of energy per day. The patients receiving the placebo meanwhile only saw an increase of +0.42 EI units (65 kcal/day). Valacyclovir therefore was almost twice as effective at improving patients' physical functioning capacity than the placebo.
The researchers go on to report that patients in the valacyclovir continued to improve progressively up to the thirty-month mark. Over this period the patients experienced steady improvemnt in energy and functioning capacity, their levels of EBV specific antibodies decreased indicating that the virus was being successfully fended off, and instances of abnormal cardiac (heart) events decreased. Patients improved so much that many were able to resume normal activities.
This is not the first antiviral drug that has been in the news lately for its use in CFS patients. Recently Ampligen moved a step closer to becoming the first officially approved medication for the treatment of CFS. Ampligen is a broad-spectrum antiviral which has been touted as a promising treatment for CFS for more than a decade but its approval has previously been held up for various reasons. Manufacturer Hemispherx Biopharma, Inc. has now filed new drug applications for the drug in a number of countries and is said to be backing this with documentation of successful trials involved well over a thousand patients.