- Interim data demonstrate that HB‑101 is well tolerated
- HB-101 elicits T cell and B cell responses in the target population
NEW YORK and VIENNA, Austria, June 22, 2020 (GLOBE NEWSWIRE) -- HOOKIPA Pharma Inc. (NASDAQ:HOOK, &lsquo, HOOKIPA&rsquo, ))), a company developing a new class of immunotherapeutics targeting infectious diseases and cancers based on its proprietary arenavirus platform, today announced positive interim results on its prophylactic Cytomegalovirus (CMV) vaccine candidate HB‑101. HB‑101 is being investigated in a double-blind Phase 2 clinical trial (NCT03629080) to assess safety, immunogenicity and efficacy in patients receiving a kidney transplant from a live donor. HOOKIPA reported interim data on the trial’s primary endpoints, safety and B cell and T cell immunogenicity.
Trial participants were blinded and randomized 2:1 to receive either HB‑101 or placebo. Patients received either 2 or 3 doses prior to transplantation, depending on the transplantation time schedule.
Tolerability profile of HB‑101
Safety and tolerability were evaluated in 51 CMV-negative patients prior to kidney transplantation. Of the 51 patients, only eight patients (16%) across the combined, blinded HB-101 and placebo groups showed adverse events related to the administration. Most of these adverse events were of mild intensity, indicating that HB‑101 is generally well tolerated in this patient population. Of note, this target patient population reported fewer adverse events than the 54 healthy volunteers in HOOKIPA’s recently published Phase 1 trial results1.
CMV-neutralizing antibody response to HB‑101
For the interim analysis, CMV-neutralizing antibody titers on the day of transplantation were evaluated in all of the 30 CMV-negative patients who had been transplanted by the cutoff date and had valid results. Nineteen of the 30 patients received HB-101 and eleven received placebo. All five patients (100%) who received three doses of HB‑101 mounted CMV-neutralizing antibodies. Three of the fourteen patients (21%) who received only two doses of HB‑101 also mounted CMV-neutralizing antibodies. The antibody response of the kidney transplant recipients who completed the three-dose regimen was comparable to the antibody response observed in the Phase 1 trial.
T cell responses to HB-101
Cellular immune responses to CMV on the day of transplantation were evaluated in 25 CMV-negative patients who had been transplanted in time for this interim analysis. Technically valid results from T cell assays on the day of transplantation were available for seven recipients (as a consequence of sample logistics and assay performance). Two of the seven patients received placebo and five received HB‑101. All three patients (100%) who received three doses of HB‑101 and one of the two patients who received only two doses (50%) mounted a CMV-specific cellular immune response.
The interim data demonstrate that HB‑101 is well tolerated with fewer adverse events in patients with end-stage kidney disease than in the previous healthy volunteer trial. Patients who received three doses of HB‑101 show comparable immunogenicity to healthy volunteers in HOOKIPA’s Phase 1 clinical trial of HB‑101.
“The interim results demonstrate that the vaccine is well-tolerated and immunogenic in patients with end-stage kidney disease,” said Joern Aldag, CEO. “We are excited that we are seeing strong antibody and T cell responses, in particular in patients who received three administrations. We continue patient accrual and plan to report preliminary efficacy data and updated safety and immunogenicity data by the end of 2020.”