Rabiës pre exposure prophylaxis in patients with auto-immune diseases using immunosuppressive agents.

Rabies is a neglected disease with a case-fatality rate of almost 100% in humans who develop symptoms. In 99% of human rabies, transmission is due to the bite of a rabies-infected dog. Rabies is fully preventable through the administration of rabies vaccines and rabies immunoglobulins (RIG).
After a potential exposure to rabies in a healthy unvaccinated person, post exposure prophylaxis (PEP) treatment consists of four rabies immunizations and RIG. By contrast, healthy persons who previously received rabies pre-exposure prophylaxis (PrEP) can suffice with a shortened PEP schedule, consisting of only two vaccinations without RIG.
For ICPs however, there are insufficient data on immunogenicity and boostability of this PrEP schedule. The recommended PrEP schedule for ICPs currently consists of three doses of rabies vaccine (days 0, 7, 21-28). For ICPs, however, adequately administered PreP does not preclude the need for RIG after a potential rabies exposure. Therefore, rabies PrEP currently does not benefit ICP travelers as much as healthy travelers. The goal of this study is to investigate the immune response after 3 doses of rabies vaccine (PrEP; day 0,7,21-28) and boostability 1 year after PrEP by admnistering 2 doses rabies vaccine (PEP; year 1 and year 1+3 days) in patients with auto-immune diseases using TNF-alpha inhibitor or DMARD monotherapy. Antibody levels will be measured by The Rapid Focus Fluorescent Inhibition Test (RFFIT).
Antibody levels above 0.5IU/L will be considered as adequate according to WHO definitions.

Rabies vaccine is very immunogenic in healthy people. The WHO considers a post-vaccination antibody titer of at minimum 0.5 IU/ml as adequate cut-off for successful vaccination. Case reports show adequate rabies antibody responses (RAR) after vaccination in ICPs using immunosuppressive therapy.
We hypothesize that in patients with auto-inflammatory diseases treated with immunosuppressive monotherapy, the immunogenicity and boostability following a 3-dose PrEP schedule is sufficient to safely recommend a shortened PEP schedule without RIG, following potential rabies exposure.

Day 0, day 7, day 21-28, day 60, month 12, month 12+3 and month 12+ 7

We offer all eligible ICPs a three-dose rabies PrEP schedule on days 0, 7 and 21-28 intramuscularly, according to the current WHO guidelines for ICPs.
At month 12, a 2-dose rabies PEP schedule will be administered intramuscularly at day 0 and day 3. Serum samples will be taken on day 0, day 28, day 60, month 12 and month 12+ 7 days to determine rabies antibody levels.
The Rapid Focus Fluorescent Inhibition Test (RFFIT) is considered the gold standard to determine rabies antibodies. All blood samples will be sent to an external rabies reference center for RFFIT. Antibody levels above 0.5IU/L will be considered as adequate according to WHO definitions.