Natural killer cytotoxicity in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): a multi-site clinical assessment of ME/CFS (MCAM) sub-study

Abstract:

Background: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a multisystem illness characterized by substantial reduction in function accompanied by profound unexplained fatigue not significantly relieved by rest, post-exertional malaise, and other symptoms. Reduced natural killer (NK) cell count and cytotoxicity has been investigated as a biomarker for ME/CFS, but few clinical laboratories offer the test and multi-site verification studies have not been conducted.

Methods: We determined NK cell counts and cytotoxicity in 174 (65%) ME/CFS, 86 (32%) healthy control (HC) and 10 (3.7%) participants with other fatigue associated conditions (ill control [IC]) from the Multi-Site Clinical Assessment of ME/CFS (MCAM) study using an assay validated for samples shipped overnight instead of testing on day of venipuncture.

Results: We found a large variation in percent cytotoxicity [mean and (IQR) for ME/CFS and HC respectively, 34.1% (IQR 22.4-44.3%) and 33.6% (IQR 22.9-43.7%)] and no statistically significant differences between patients with ME/CFS and HC (p-value = 0.79). Analysis stratified on illness domain measured with standardized questionnaires did not identify an association of NK cytotoxicity with domain scores. Among all participants, NK cytotoxicity was not associated with survey results of physical and mental well-being, or health factors such as history of infection, obesity, smoking, and co-morbid conditions.

Conclusion: These results indicate this assay is not ready for clinical implementation and studies are needed to further explore immune parameters that may be involved in the pathophysiology of ME/CFS.

Source: Querec TD, Lin JS, Chen Y, Helton B, Kogelnik AM, Klimas NG, Peterson DL, Bateman L, Lapp C, Podell RN, Natelson BH, Unger ER; MCAM Study Group. Natural killer cytotoxicity in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): a multi-site clinical assessment of ME/CFS (MCAM) sub-study. J Transl Med. 2023 Apr 3;21(1):242. doi: 10.1186/s12967-023-03958-2. PMID: 37013608. https://translational-medicine.biomedcentral.com/articles/10.1186/s12967-023-03958-2 (Full text)

Multi-Site Clinical Assessment of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (MCAM): Design and Implementation of a Prospective/Retrospective Rolling Cohort Study

Abstract:

In the Multi-Site Clinical Assessment of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (MCAM), we relied on expert clinician diagnoses to enroll patients from 7 specialty clinics in the United States in order to perform a systematic collection of data on measures of myalgic encephalomyelitis (ME)/chronic fatigue syndrome (CFS). Healthy persons and those with other illnesses that share some features with ME/CFS were enrolled in comparison groups. The major objectives were to:

1) use standardized questionnaires to measure illness domains of ME/CFS and to evaluate patient heterogeneity overall and between clinics;

2) describe the course of illness, identify the measures that best correlate with meaningful clinical differences, and assess the performances of questionnaires as patient/person-reported outcome measures;

3) describe prescribed medications, orders for laboratory and other tests, and management tools used by expert clinicians to care for persons with ME/CFS;

4) collect biospecimens for future hypothesis testing and for evaluation of morning cortisol profiles; and

5) identify measures that best distinguish persons with ME/CFS from those in the comparison groups and detect subgroups of persons with ME/CFS who may have different underlying causes.

Enrollment began in 2012 and is planned to continue in multiple stages through 2017. We present the MCAM methods in detail, along with an initial description of the 471 patients with ME/CFS who were enrolled in stage 1.

Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US

 

Source: Unger ER, Lin JS, Tian H, Natelson BH, Lange G, Vu D, Blate M, Klimas NG, Balbin EG, Bateman L, Allen A, Lapp CW, Springs W, Kogelnik AM, Phan CC, Danver J, Podell RN, Fitzpatrick T, Peterson DL, Gottschalk CG, Rajeevan MS; MCAM Study Group. Multi-Site Clinical Assessment of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (MCAM): Design and Implementation of a Prospective/Retrospective Rolling Cohort Study. Am J Epidemiol. 2017 Mar 17:1-10. doi: 10.1093/aje/kwx029. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/28338983

 

New Therapy For Chronic Fatigue Syndrome To Be Tested

Press Release: A preliminary study suggests there may be hope in the offing for some sufferers of chronic fatigue syndrome with a new therapy being tested by researchers at the Stanford University School of Medicine.

José Montoya, MD, associate professor of medicine (infectious diseases), and postdoctoral scholar Andreas Kogelnik, MD, PhD, have used the drug valganciclovir – an antiviral often used in treating diseases caused by human herpes viruses – to treat a small number of CFS patients.

The researchers said they treated 25 patients during the last three years, 21 of whom responded with significant improvement that was sustained even after going off the medication at the end of the treatment regimen, which usually lasts six months. The first patient has now been off the drug for almost three years and has had no relapses. A paper describing the first dozen patients Montoya and Kogelnik treated with the drug was published in the December issue of Journal of Clinical Virology.

“This study is small and preliminary, but potentially very important,” said Anthony Komaroff, MD, professor of medicine at Harvard Medical School, who was not involved in the study. “If a randomized trial confirmed the value of this therapy for patients like the ones studied here, it would be an important landmark in the treatment of this illness.”

Montoya has received a $1.3 million grant from Roche Pharmaceutical, which manufactures the drug under the brand name Valcyte, to conduct a randomized, placebo-controlled, double-blind study set to begin this quarter at Stanford. The study will assess the effectiveness of the drug in treating a subset of CFS patients.

Montoya is speaking about his efforts at the biannual meeting of the International Association for Chronic Fatigue Syndrome in Fort Lauderdale on Jan. 11 and 12.

Chronic fatigue syndrome has baffled doctors and researchers for decades, because aside from debilitating fatigue, it lacks consistent symptoms. Although many genetic, infectious, psychiatric and environmental factors have been proposed as possible causes, none has been nailed down. It was often derided as “yuppie flu,” since it seemed to occur frequently in young professionals, though the Centers for Disease Control and Prevention says it’s most common in the middle-aged. But to those suffering from it, CFS is all too real and its effects are devastating, reducing once-vigorous individuals to the ranks of the bedridden, with an all-encompassing, painful and sleep-depriving fatigue.

More than 1 million Americans suffer from the disorder, according to the CDC. The disease often begins with what appears to be routine flulike symptoms, but then fails to subside completely – resulting in chronic, waxing and waning debilitation for years.

Valganciclovir is normally used against diseases caused by viruses in the herpes family, including cytomegalovirus, Epstein-Barr virus and human herpes virus-6. These diseases usually affect patients whose immune systems are severely weakened, such as transplant and cancer patients. Montoya, who had used the drug in treating such patients for years, decided to try using it on a CFS patient who came to him in early 2004 with extremely high levels of antibodies for three of the herpes family viruses in her blood. At the time, she had been suffering from CFS for five years.

When a virus infects someone, the levels of antibodies cranked out by the immune system in response typically increase until the virus is overcome, then slowly diminish over time. But Montoya’s patient had persistently high antibodies for the three viruses. In addition, the lymph nodes in her neck were significantly enlarged, some up to eight times their normal size, suggesting her immune system was fighting some kind of infection, even though a comprehensive evaluation had failed to point to any infectious cause.

Concerned about the unusual elevations in antibody levels as well as the swelling of her lymph nodes, Montoya decided to prescribe valganciclovir. “I thought by giving an antiviral that was effective against herpes viruses for a relatively long period of time, perhaps we could impact somehow the inflammation that she had in her lymph nodes,” said Montoya.

Within four weeks, the patient’s lymph nodes began shrinking. Six weeks later she phoned Montoya from her home in South America, describing how she was now exercising, bicycling and going back to work at the company she ran before her illness. “We were really shocked by this,” recalled Montoya.

Of the two dozen patients Montoya and Kogelnik have since treated, the 20 that responded all had developed CFS after an initial flulike illness, while the non-responders had suffered no initial flu.

Some of the patients take the drug for more than six months, such as Michael Manson, whose battle with CFS has lasted more than 18 years. The former triathlete was stricken with a viral infection a year after his marriage. After trying unsuccessfully to overcome what he thought were lingering effects of the flu, he had no choice but to drastically curtail all his activities and eventually stop working.

During his longest period of extreme fatigue, 13 1/2 weeks, Manson said, “My wife literally thought I was passing away. I could hear the emotion in her voice as she tried to wake me, but I couldn’t wake up to console her. That was just maddening.”

Now in his seventh month of treatment, Manson is able to go backpacking with his children with no ill after-effects. Prior to starting the treatment, Manson’s three children, ages 9 to 14, had never seen him healthy.

Montoya and Kogelnik emphasized that even if their new clinical trial validates the use of valganciclovir in treating some CFS patients, the drug may not be effective in all cases. In fact, the trial will assess the effectiveness of the medication among a specific subset of CFS patients; namely, those who have viral-induced dysfunction of the central nervous system.

“This could be a solution for a subset of patients, but that subset could be quite large,” said Kristin Loomis, executive director of the HHV-6 Foundation, which has helped fund a significant portion of the preparatory work for the clinical trial. “These viruses have been suspected in CFS for decades, but researchers couldn’t prove it because they are so difficult to detect in the blood. If Montoya’s results are confirmed, he will have made a real breakthrough.”

“What is desperately needed is the completion of the randomized, double-blind, placebo-controlled clinical trial that we are about to embark on,” Montoya said.

 

Source: Stanford University Medical Center. “New Therapy For Chronic Fatigue Syndrome To Be Tested.” ScienceDaily. ScienceDaily, 9 January 2007. https://www.sciencedaily.com/releases/2007/01/070108191506.htm

 

Randomized clinical trial to evaluate the efficacy and safety of valganciclovir in a subset of patients with chronic fatigue syndrome

Abstract:

There is no known treatment for chronic fatigue syndrome (CFS). Little is known about its pathogenesis. Human herpesvirus 6 (HHV-6) and Epstein-Barr virus (EBV) have been proposed as infectious triggers.

Thirty CFS patients with elevated IgG antibody titers against HHV-6 and EBV were randomized 2:1 to receive valganciclovir (VGCV) or placebo for 6 months in a double-blind, placebo-controlled trial. Clinical endpoints aimed at measuring physical and mental fatigue included the Multidimensional Fatigue Inventory (MFI-20) and Fatigue Severity Scale (FSS) scores, self-reported cognitive function, and physician-determined responder status. Biological endpoints included monocyte and neutrophil counts and cytokine levels.

VGCV patients experienced a greater improvement by MFI-20 at 9 months from baseline compared to placebo patients but this difference was not statistically significant. However, statistically significant differences in trajectories between groups were observed in MFI-20 mental fatigue subscore (P = 0.039), FSS score (P = 0.006), and cognitive function (P = 0.025). VGCV patients experienced these improvements within the first 3 months and maintained that benefit over the remaining 9 months. Patients in the VGCV arm were 7.4 times more likely to be classified as responders (P = 0.029). In the VGCV arm, monocyte counts decreased (P < 0.001), neutrophil counts increased (P = 0.037) and cytokines were more likely to evolve towards a Th1-profile (P < 0.001). Viral IgG antibody titers did not differ between arms.

VGCV may have clinical benefit in a subset of CFS patients independent of placebo effect, possibly mediated by immunomodulation and/or antiviral effect. Further investigation with longer treatment duration and a larger sample size is warranted.

TRIAL REGISTRATION: ClinicalTrials.gov NCT00478465.

© 2013 Wiley Periodicals, Inc.

 

Source: Montoya JG, Kogelnik AM, Bhangoo M, Lunn MR, Flamand L, Merrihew LE, Watt T, Kubo JT, Paik J, Desai M. Randomized clinical trial to evaluate the efficacy and safety of valganciclovir in a subset of patients with chronic fatigue syndrome. J Med Virol. 2013 Dec;85(12):2101-9. doi: 10.1002/jmv.23713. Epub 2013 Aug 19. https://www.ncbi.nlm.nih.gov/pubmed/23959519

 

Use of valganciclovir in patients with elevated antibody titers against Human Herpesvirus-6 (HHV-6) and Epstein-Barr Virus (EBV) who were experiencing central nervous system dysfunction including long-standing fatigue

Abstract:

BACKGROUND:Twelve patients with long-standing symptoms of central nervous system (CNS) dysfunction were found to have elevated antibody titres to human herpesvirus-6 (HHV-6) and Epstein-Barr virus (EBV). All patients had four or more of the following neurocognitive symptoms: impaired cognitive functioning, slowed processing speed, sleep disturbance, short-term memory deficit, fatigue and symptoms consistent with depression.

OBJECTIVES: We sought to determine whether elevated antibodies to EBV and HHV-6 indicated chronic viral activation in patients with CNS dysfunction and if their symptoms could be improved by suppressing viral activity with oral valganciclovir.

STUDY DESIGN: Patients with high IgG antibody titers against HHV-6 and EBV who were suffering from central nervous system dysfunction and debilitating fatigue for more than one year (median 3 years, range 1-8 years) were treated with 6 months of valganciclovir in an open label study.

RESULTS: Nine out of 12 (75%) patients experienced near resolution of their symptoms, allowing them all to return to the workforce or full time activites. In the nine patients with a symptomatic response to treatment, EBV VCA IgG titers dropped from 1:2560 to 1:640 (p = 0.008) and HHV-6 IgG titers dropped from a median value of 1:1280 to 1:320 (p = 0.271). Clinically significant hematological toxicity or serious adverse events were not observed among the 12 patients.

CONCLUSION: These preliminary clinical and laboratory observations merit additional studies to establish whether this clinical response is mediated by an antiviral effect of the drug, indirectly via immunomodulation or by placebo effect.

 

Source: Kogelnik AM, Loomis K, Hoegh-Petersen M, Rosso F, Hischier C, Montoya JG. Use of valganciclovir in patients with elevated antibody titers against Human Herpesvirus-6 (HHV-6) and Epstein-Barr Virus (EBV) who were experiencing central nervous system dysfunction including long-standing fatigue. J Clin Virol. 2006 Dec;37 Suppl 1:S33-8. https://www.ncbi.nlm.nih.gov/pubmed/17276366