FDA gives herpes zoster vaccine the OK

June 2006

The FDA licensed a live herpes zoster vaccine (Zostavax, Oka/Merck) for prevention of shingles in people aged 60 and older.

In trials, the new vaccine demonstrated it could boost immunity against varicella-zoster virus.

“This vaccine gives health care providers an important tool that can help prevent an illness that affects many older Americans and often results in significant chronic pain,” Jesse L. Goodman, MD, MPH, director of the FDA’s Center for Biologics Evaluation and Research, said in a prepared statement.

Researchers studied the vaccine in approximately 38,000 people throughout the United States aged 60 and older. Half the study population received the vaccine, the other half placebo. All participants were followed an average of three years to examine whether they developed shingles and if they did, how long the pain lasted.

Researchers concluded the vaccine reduced the occurrence of shingles by about 50%, and for people aged 60 to 69, it reduced occurrence by 64%.

In addition to preventing approximately half the shingles cases, the duration of pain following the onset of disease was slightly reduced in people who developed the disease despite vaccination.

Researchers also conducted a smaller study to examine safety. They noted more frequent serious adverse events for all age groups who received the vaccine (1.9%) than those who received placebo (1.3%). The FDA concluded that the available data do not establish the events as related to the vaccine, but the manufacturer will perform a phase-4, postmarket study to provide additional safety information.

“This vaccine is clinically important because it can prevent a disease that may cause pain in some patients,” Ann Arvin, MD, professor of pediatrics, infectious diseases and microbiology and immunology at the Stanford University School of medicine, said in a Merck press release. “Zostavax is unique because in contrast to other vaccines that help prevent a primary infection, Zostavax helps prevent reactivation of a virus that’s already inside the body.”

The vaccine and shingles

The varicella-zoster virus that causes shingles also causes chickenpox. After an attack of chickenpox, the virus lies dormant in certain nerve tissue and as people age, the virus can reappear as shingles.

Shingles usually starts as an unusual or painful sensation on one side of the body or face, followed by a blistering rash. Pain is mild to severe and may occur before and after the rash, and as postherpetic neuralgia. Other complications, such as scarring, allodynia, pneumonia, visual impairment and hearing loss can also occur.

Researchers have not evaluated safety and efficacy in people who are immunosuppressed, or in people who receive daily topical or inhaled corticosteroids, or low-dose oral corticosteroids. Researchers have not studied the vaccine in people with a history of shingles.

The vaccine is contraindicated in people with a history of anaphylactic/anaphylactoid reaction to gelatin, neomycin or any other component of the vaccine; with a history of primary or acquired immunodeficiency states including leukemia, lymphomas of any type or other malignant neoplasms affecting the bone marrow or lymphatic system; with AIDS or other clinical manifestations of infection with HIV; and with active, untreated tuberculosis.