LAUSR

Abstract Background No herpes zoster (HZ) vaccine for immunosuppressed individuals is currently available. GSK’s candidate HZ vaccine containing recombinant varicella zoster virus glycoprotein E (gE) subunit and AS01B Adjuvant System (HZ/su) showed >90% efficacy for HZ prevention in immunocompetent adults aged ≥50 years. The HZ incidence in individuals with solid tumors (ST) receiving immunosuppressive chemotherapy (chemo) is estimated as 3–4 times higher than in the overall US population (3.2/1000 person-years). We present HZ/su immunogenicity and safety in ST adults aged ≥18 years. Methods In this phase II/III, observer-blind, multicenter study (NCT01798056), ST adults received 2 doses of HZ/su or placebo intramuscularly 1–2 months apart and were randomized 4:4:1:1 to receive a first dose 8–30 days (D) pre-chemo (HZ/su – HZ/su-PreC group, placebo – Pl-PreC) or on chemo start (±1 D) (HZ/su-OnC, Pl-OnC). Vaccine response rates (VRRs) and geometric means (GMs)/means were evaluated for gE humoral immune and gE-specific CD4+ cell-mediated immune (CMI) responses 1 month (M2) and 12 months (M13) post-dose 2. Solicited adverse events (AEs) were recorded for 7 D and unsolicited and medically-attended AEs (MAEs) for 30 D post each dose. Potential immune-mediated diseases (pIMDs) and serious AEs (SAEs) were recorded until study end. Results 185 subjects (65 HZ/su-PreC, 78 Pl-PreC, 22 HZ/su-OnC, 20 Pl-OnC) were included in the according-to-protocol (ATP) cohort for humoral immunogenicity and 58 (27 HZ/su-PreC, 31 Pl-PreC) in the ATP sub-cohort for CMI. The most common ST were breast tumors (54% HZ/su, 49% placebo), followed by colorectal, lung, then other. Humoral and CMI VRRs were higher in HZ/su than Pl groups at M2 and M13. GM concentration (GMC) was highest at M2 in HZ/su-PreC. M13 GMCs were similar in the HZ/su-PreC and HZ/su-OnC groups (Table 1). The frequency of local solicited AEs was higher in HZ/su than Pl groups (Table 2); that of general solicited, unsolicited AEs, MAEs and SAEs was similar among groups (Table 3). 1 pIMD (Pl-OnC) and 23 fatal SAEs were reported. No SAE was considered vaccine-related by investigators. Conclusion HZ/su was highly immunogenic in ST adults receiving chemo. No safety concerns were raised. Funding GlaxoSmithKline Biologicals SA Disclosures P. Vink, GSK group of companies: Employee, Salary and stock options and stock granted