This study was a randomized, placebo-controlled, parallel group, patient-blinded, two centre study, assessing tolerability and safety of repeated subcutaneous (s.c.) administration of two doses of AFFITOPE® PD03A formulated with adjuvant to patients with early Parkinson’s disease (PD). Thirty-six patients were randomized to either AFFITOPE® PD03A high dose (75μg), low dose (15μg) or to the placebo group treated with adjuvant alone. Patients received 5 injections, 4 for priming every 4 weeks and the 5th as boost immunization 9 months after the first immunization. Key objectives were to show safety and tolerability as well as immunogenicity of AFFITOPE® PD03A. At screening, the average time of PD after first diagnosis was between 1.6-2.3 years; patients were allowed to continue their standard of care PD medication.
Affiris is taking a different approach of active vaccination to induce an antibody response, rather than passive antIbody delivery. There are potential advantages and disadvantages of such an approach. On the positive side the antibodies will bind specifically to a relevant appropriate target and they can be calibrated for specificity and selectivity of the immune response. In addition the drug is delived subcutaneously rather than intravenously and boosts can be done to further induce immune response. The potential pitfalls are lack of accurate prespecified level of immune response in a given individual and as such potential safety concerns though none have been seen so far in the early programs. The Michael J Fox Foundation has reported that Affiris is planning a Phase 2 study.
Both doses were locally and systemically well tolerated. No study drug related SAE or SUSAR occurred. AFFITOPE® PD03A showed a clear dose dependent immune response against the peptide itself and cross-reactivity against the aSyn targeted epitope over time, with antibody reactivation upon booster immunization. A parallel Phase 1 study (NCT02270489; AFF009) evaluated high dose (75μg) AFFITOPE® PD01A and PD03A in patients with MSA. Both doses were safe and well-tolerated. PD01A showed a clear immune response but, in contrast to the results in the PD trial, PD03A showed no difference to placebo.