P98-39 FOOD AND DRUG ADMINISTRATION FOR IMMEDIATE RELEASE Print Media: 301-827-6242 December 21, 1998 Consumer Media: 888-Info-FDA
Although Lymerix may provide protection for a majority of people, it does not prevent all cases of Lyme disease. Therefore, people should continue to take standard preventive measures against infection, including wearing protective clothing, using tick repellent and removing attached ticks.
Lymerix contains a genetically engineered protein from an outer surface protein of B. burgdorferi, the spiral shaped bacterium that is responsible for Lyme disease. The surface protein, called OspA, stimulates antibodies that appear to disable the bacterium's ability to infect the individual.
"For people who spend a lot of time outdoors in areas where Lyme disease is common, this new vaccine may be a good option," said Dr. Jane E. Henney, FDA Commissioner. "However, this vaccine's effectiveness depends on people getting all three doses over the period of a year. We also want to emphasize that the vaccine is not 100% effective, so other precautions should be taken."
Lyme disease, which is rarely fatal, typically (but not always) causes a characteristic "bull's eye" rash and flu-like symptoms in the early stages of infection, and occasionally facial weakness and heart problems. In the later stages of the disease, months or years later, some patients may have chronic arthritis or neurologic problems.
Since the Centers for Disease Control and Prevention (CDC) first began tracking cases for Lyme disease in the U.S. in 1982, over 99,000 cases have been reported. More than 16,000 cases were reported by 45 states to CDC in 1996, the last year for which complete statistics are available. Most cases in the U.S. have been reported in the Northeast, upper Midwest and Pacific coastal states.
The randomized, multi centered, placebo-controlled trial of Lymerix involved almost 11,000 people between 15 and 70 years of age, and was conducted in the northeast U.S. and Wisconsin, where Lyme disease is common. Individuals received three doses of vaccine at 0, 1, and 12 months, and then were followed for 20 months after the first injection or through two tick seasons. After two doses of the vaccine in the first year of the trial, the protection rate against definite Lyme Disease was 50% and in the second year, after three doses, it was 78%.
The time of year when people get vaccinated with Lymerix may be important. In the clinical trial, conducted over two years in the northeast U.S, safety and efficacy were shown when the vaccine doses were given between January and April, shortly before the peak tick season in the northeast U.S. It is not currently known how long protection against Lyme disease lasts after vaccination.
The vaccine was given to healthy individuals, and was generally well tolerated. Local injection site reactions, including redness, soreness, and swelling, were common. Most other adverse events, such as flu-like symptoms and muscle and joint pain, occurred less frequently and were mild to moderate.
People were excluded from the clinical trial if they were pregnant or if they had chronic joint or neurologic illnesses related to Lyme disease, diseases such as rheumatoid arthritis associated with joint swelling, or certain heart conditions. Therefore, limited safety data are available for these individuals.
No data are available for people under 15 or over 70 years of age. The vaccine is not currently approved for use in children less than 15 years of age.
Lymerix will be marketed by SmithKline Beecham Pharmaceuticals, Philadelphia, PA.