In December 2018, we reported on a study that found higher risk of herpes zoster, or shingles, in certain cancer patients, and discussed the roles that vaccine development could potentially play in preventing these painful episodes. Here, we examine research on zoster vaccines in immunocompromised patient populations appearing after that initial study was published.
In November, Clinical Infectious Diseases published a systematic review of 34 studies that examined risk of herpes zoster among patients with hematopoietic cell transplants, hematologic and solid tumors, as well as solid tumor malignancies, and other immunocompromised populations, such as HIV. The authors found estimates of herpes zoster incidence ranging from 9 to 92 cases/1,000 patient-years. Similar to the December 2018 study, the CID authors found incidence was higher in patients with hematopoietic cell transplants, followed by solid organ transplant and solid tumor malignancies.
In February, The Lancet Infectious Diseases published a summary of guidelines from the most recent European Conference on Infections in Leukaemia about vaccination in patients with hematologic malignancies who did not have transplantations.
Examining patients with multiple myeloma, the authors recommended valacyclovir prophylaxis, an antiviral used to treat active infections including shingles. Zoster live attenuated vaccine is contraindicated in such patients, the authors noted, and there are no data in this population yet about an approved inactivated subunit vaccine, though it is “much awaited” for these patients.
The guidelines also observed that there are no data on either the live attenuated or the inactivated vaccine among patients with chronic lymphocytic leukemia, despite their elevated risk for zoster attacks.
“The inactivated zoster vaccines should be assessed in adult and child patients with [hematological] disorders,” the authors said.
Researchers continued to examine the role of inactivated vaccines against herpes zoster in patients with solid tumor malignancies. A study published in August found that an inactivated varicella zoster virus vaccine was effective, meeting pre-specified criteria for preventing confirmed herpes zoster infection in patients with solid tumor malignancies who were receiving chemotherapy. However, the vaccine was not effective in patients with hematologic malignancies.
But a second study found that the adjuvanted recombinant zoster vaccine, Shingrix, produced an immunologic response in a cohort of adult patients with hematological malignancies during or soon after they underwent cancer treatment compared to placebo.
Adding to the evidence for the effectiveness of Shingrix, a July study also found that patients undergoing autologous hematopoietic stem cell transplantation who received the vaccine had lower incidence of shingles versus patients who received placebo.
Alison Freifeld, MD, of the University of Nebraska Medical Center in Omaha, who was not involved in the research, told MedPage Today in July that transplant patients couldn’t receive the zoster vaccine until at least 2 years after transplantation, due to the potential risk of a patient developing disseminated vaccine strain live virus.
“[Shingrix] is a great advantage for autologous transplant patients because it permits the vaccine to be given much earlier than the previous live virus vaccine,” she said.
Jeanne Marrazzo, MD, of the University of Alabama at Birmingham, told MedPage Today at that time that “protection was less than that observed in immune-competent people, which the investigators attribute to a generally weaker immune system in the HSCT recipients.”
“Regardless, this outcome is considerably better than no vaccine, which was the earlier alternative,” Marrazzo added.
In addition to cancer patients, researchers continued to discuss the use of both live-attenuated vaccines and inactivated vaccines among immunocompromised populations, such as patients with autoimmune conditions.
And research presented at the American College of Rheumatology annual meeting in November provided reassuring evidence about the safety of live attenuated herpes zoster vaccine, Zostavax, among patients treated with tumor necrosis factor inhibitors. A randomized trial found that no patients developed varicella (chicken pox, the predecessor to shingles) infections or shingles attacks, and there was no difference in rates of rheumatologic disease flare between groups receiving vaccine or placebo.
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