Robert S. Janssen

Immunogenicity and safety of an investigational hepatitis B vaccine with a Toll-like receptor 9 agonist adjuvant (HBsAg-1018) compared to a licensed hepatitis B vaccine in healthy adults 40–70 years of age☆

BACKGROUNDnThe currently licensed hepatitis B vaccines have limitations including hyporesponsiveness in older adults, poor compliance, and the extended time for most persons to develop seroprotection (e.g. >6months). A vaccine containing HBsAg combined with a Toll-like receptor 9 agonist adjuvant (HBsAg-1018) has been developed to overcome these limitations.nnnMETHODSnA Phase 3, multicenter, randomized, subject- and observer-blinded, active-controlled trial was conducted among healthy subjects 40-70years of age comparing the immunogenicity and safety of two doses of HBsAg-1018 at 0 and 4weeks to three doses of licensed hepatitis B vaccine, HBsAg-Eng, at 0, 4, and 24weeks. The primary immunogenicity endpoint was noninferiority of the seroprotection rate (SPR; % with anti-HBs≥10mIU/mL) of HBsAg-1018 compared to the SPR of HBsAg-Eng at 8 weeks following the last dose of vaccine. Conditional upon meeting noninferiority, superiority of HBsAg-1018 over HBsAg-Eng was assessed. Safety was compared between the two vaccines.nnnRESULTSnAt the primary endpoint, the SPR for the HBsAg-1018 group (90.0%) was superior to the SPR for the HBsAg-Eng group (70.5%) with an SPR difference of 19.5% (95% CI, 14.7%, 24.7%). At week 28 when the SPR peaked in the HBsAg-Eng group (72.8%), the SPR in the HBsAg-1018 group (94.8%) was significantly higher than in the HBsAg-Eng group. The SPR in the HBsAg-1018 group was significantly higher than in the HBsAg-Eng group at each study visit from week 4 through week 52. The safety profiles for the two vaccines were similar.nnnCONCLUSIONnWhen compared to the HBsAg-Eng three-dose regimen given at 0, 1, and 6months, HBsAg-1018 demonstrated superior seroprotection with only two doses at 0 and 1month. The safety profile of HBsAg-1018 was comparable to that of the licensed vaccine, HBsAg-Eng. HBsAg-1018 would provide a significant public health contribution toward the prevention of hepatitis B infection.

Immunogenicity and safety of an investigational hepatitis B vaccine with a toll-like receptor 9 agonist adjuvant (HBsAg-1018) compared with a licensed hepatitis B vaccine in patients with chronic kidney disease

BACKGROUNDnHemodialysis patients are at increased risk of hepatitis B virus (HBV) infection and patients with chronic kidney disease (CKD) are commonly hyporesponsive to HBV vaccines. Current recommendations for CKD patients are to utilize 4 double-doses (2×20 mcg HBsAg) of a licensed hepatitis B vaccine (HBsAg-Eng).nnnMETHODSnAn observer-blind, randomized, active-controlled, parallel group, multicenter trial was conducted among 521 patients 18-75 years of age with CKD, comparing 3 single doses of an investigational hepatitis B vaccine (20 mcg rHBsAg+3000 mcg 1018, a toll-like receptor 9 agonist) given at 0, 4, and 24 weeks to 4 double-doses of HBsAg-Eng (2×20 mcg rHBsAg+500 mcg alum) given at 0, 4, 8, and 24 weeks (total of 8 injections). Participants were followed for 1 year.nnnRESULTSnAmong 467 participants in the modified intent-to-treat population, at the primary endpoint at week 28, the seroprotection rate (SPR: % with anti-HBs≥10mIU/mL) in the HBsAg-1018 group (89.9%) met criteria for noninferiority and superiority to the SPR in the HBsAg-Eng group (81.8%). At week 28, the percentage of participants with anti-HBs≥100mIU/mL in the HBsAg-1018 group (73.6%) was significantly higher than in the HBsAg-Eng group (63.2%). In addition, the geometric mean concentration of anti-HBs in the HBsAg-1018 group (587.1mIU/mL) was significantly higher than in the HBsAg-Eng group (156.5mIU/mL). At weeks 8 and 12 after the first study injection, SPRs in the HBsAg-1018 group were significantly higher than in the HBsAg-Eng group. At 52 weeks, the immune response to HBsAg-1018 remained higher than to HBsAg-Eng. HBsAg-1018 was generally well tolerated and had a similar safety profile to HBsAg-Eng.nnnCONCLUSIONnIn CKD patients, 3 doses of HBsAg-1018 induced significantly higher seroprotection, earlier seroprotection, and more durable seroprotection than 4 double doses of HBsAg-Eng.

Cost-effectiveness of hepatitis B vaccination using HEPLISAV™ in selected adult populations compared to Engerix-B® vaccine

OBJECTIVEnHEPLISAV™ is an adult hepatitis B vaccine that requires fewer doses over a shorter period of time and elicits higher and earlier seroprotection compared to Engerix-B to reduce the risk of hepatitis B infection. The objective of this analysis was to evaluate the cost-effectiveness of vaccination with HEPLISAV vs. Engerix-B(®) to prevent hepatitis B infection in select populations.nnnMETHODSnMarkov models were developed for the following populations: diabetics, patients with chronic or end stage kidney disease, healthcare workers and international travelers to countries with high HBV infection prevalence. Hepatitis B disease progression was modeled using 11 health states: seroprotected, susceptible, acute infection, chronic infection, fulminant hepatic failure, compensated cirrhosis, decompensated cirrhosis, hepatocellular carcinoma, liver transplant, post-transplant care, and death. Seroprotection rates were obtained from two phase 3 clinical trials comparing HEPLISAV with Engerix-B and ranged across various populations from 89-96% for HEPLISAV and 62-81% for Engerix-B. Higher vaccination completion rates were assumed for HEPLISAV compared with Engerix-B given that fewer doses of HEPLISAV are required in a shorter period of time to achieve seroprotection for the evaluated populations. Each cycle length after the first year in the model was 1-year. All future costs and benefits were discounted at 3%. A lifetime analysis and a U.S. payer perspective were used.nnnRESULTSnHEPLISAV has a favorable cost-effectiveness profile with incremental cost effectiveness ratios <

Immunogenicity of a two-dose investigational hepatitis B vaccine, HBsAg-1018, using a toll-like receptor 9 agonist adjuvant compared with a licensed hepatitis B vaccine in adults

25,000 across all populations studied. In the patients with chronic or end stage kidney disease, HEPLISAV was the dominant option and was cost-saving compared with Engerix-B. The cost of vaccine, regimen completion rates, and seroprotection rates were the sensitive variables in the models.nnnCONCLUSIONSnHEPLISAV is a cost-effective option to provide high rates of seroprotection and early seroprotection across a range of populations from health care workers to patients with chronic or end stage kidney disease.

Immunogenicity of an investigational hepatitis B vaccine with a toll-like receptor 9 agonist adjuvant (HBsAg-1018) compared with a licensed hepatitis B vaccine in subpopulations of healthy adults 18–70 years of age

BACKGROUNDnHepatitis B virus infection remains an important public health problem in the United States. Currently approved alum-adjuvanted vaccines require three doses and have reduced immunogenicity in adults, particularly in those who have diabetes mellitus, or are older, male, obese, or who smoke.nnnMETHODSnPhase 3 observer-blinded, randomized (2:1 HBsAg-1018 [HEPLISAV-B™]:HBsAg-Eng [Engerix-B®]), active-controlled trial in adults 18-70u202fyears of age. HBsAg-1018 was administered intramuscularly at weeks 0 and 4 and placebo at week 24 and HBsAg-Eng at weeks 0, 4, and 24. The primary immunogenicity endpoint assessed the noninferiority of the seroprotection rate at week 28 in participants with type 2 diabetes mellitus. Secondary endpoints included seroprotection rates in the total trial population and by age, sex, body mass index, and smoking status.nnnRESULTSnAmong 8374 participants randomized, 961 participants in the per-protocol population had type 2 diabetes mellitus. In diabetes participants, the seroprotection rate in the HBsAg-1018 group at week 28 was 90.0%, compared with 65.1% in the HBsAg-Eng group, with a difference of 24.9% (95% CI: 19.3%, 30.7%), which met the prospectively-defined criteria for noninferiority and statistical significance. In the total study per-protocol population (Nu202f=u202f6826) and each pre-specified subpopulation, the seroprotection rate in the HBsAg-1018 group was statistically significantly higher than in the HBsAg-Eng group.nnnCONCLUSIONnTwo doses of HBsAg-1018, administered over 4u202fweeks, induced significantly higher seroprotection rates than three doses of HBsAg-Eng, given over 24u202fweeks, in adults with factors known to reduce the immune response to hepatitis B vaccines as well as in those without those factors. With fewer doses in a shorter time, and greater immunogenicity, HBsAg-1018 has the potential to significantly improve protection against hepatitis B in adults at risk for hepatitis B infection. Trial Registration clinicaltrials.gov Identifier: NCT02117934.

Immunogenicity and safety of an investigational hepatitis B vaccine with a Toll-like receptor 9 agonist adjuvant (HBsAg-1018) compared with a licensed hepatitis B vaccine in patients with chronic kidney disease and type 2 diabetes mellitus

BACKGROUNDnImmunologic response to a complete vaccine regimen of currently licensed alum-adjuvanted hepatitis B vaccines is reduced in several subpopulations, including older adults, men, obese persons, and smokers. Two phase 3 trials in healthy adults demonstrated that 2 doses over 1 month of an investigational hepatitis B vaccine (HBsAg-1018) induced superior seroprotection rates (SPRs) to 3 doses over 6 months of the licensed vaccine Engerix-B (HBsAg-Eng).nnnMETHODSnAn exploratory analysis of immunogenicity was conducted in subpopulations from pooled data for the 2 phase 3 trials.nnnRESULTSnIn each subpopulation, the peak SPR in the HBsAg-1018 group was statistically significantly higher than the peak SPR in the HBsAg-Eng group. Peak HBsAg-1018 SPRs ranged from 91.6% to 99.7%, while peak HBsAg-Eng SPRs ranged from 67.7% to 92.9%.nnnCONCLUSIONnIn these exploratory analyses, 2 doses of HBsAg-1018 induced statistically significantly higher rates of seroprotection than 3 doses of HBsAg-Eng across all subpopulations.

Safety of a two-dose investigational hepatitis B vaccine, HBsAg-1018, using a toll-like receptor 9 agonist adjuvant in adults

BACKGROUNDnMany patients with chronic kidney disease (CKD) are hyporesponsive to currently licensed alum-adjuvanted hepatitis B vaccines, including Engerix-B(®) (HBsAg-Eng). Seroprotection rates (SPRs) are further reduced in CKD patients with diabetes mellitus. Three doses of an investigational hepatitis B vaccine (HBsAg-1018) that uses a Toll-like receptor 9 agonist demonstrated superior SPRs to 4 double doses of HBsAg-Eng in a large phase 3 trial of CKD patients.nnnMETHODSnA prespecified subgroup analysis of immunogenicity was conducted in CKD participants with type 2 diabetes in the phase 3 trial.nnnRESULTSnIn 328 participants, the peak SPR in the HBsAg-1018 group met criteria for noninferiority and superiority to the peak SPR in the HBsAg-Eng group. The peak geometric mean concentration of antibody against hepatitis B surface antigen in the HBsAg-1018 group was statistically significantly higher than in the HBsAg-Eng group.nnnCONCLUSIONnHBsAg-1018 induced significantly higher seroprotection than HBsAg-Eng in CKD patients with diabetes.

In Situ Vaccination with a TLR9 Agonist and Local Low-Dose Radiation Induces Systemic Responses in Untreated Indolent Lymphoma

BACKGROUNDnHepatitis B virus infection remains an important global public health problem. Approved alum-adjuvanted vaccines are well tolerated but require three doses and have reduced immunogenicity in adults. A two-dose vaccine containing hepatitis B surface antigen combined with a novel, Toll-like receptor 9 agonist adjuvant (HBsAg-1018 [HEPLISAV-B®]) has demonstrated significantly higher seroprotection rates than a three dose vaccine.nnnMETHODSnA post hoc analysis compared the safety of HBsAg-1018 with HBsAg-Eng (Engerix-B®), in three randomized, observer-blinded, active-controlled, multi-center phase 3 trials in adults. HBsAg-1018 was administered intramuscularly at weeks 0 and 4 and placebo at week 24 and HBsAg-Eng at weeks 0, 4, and 24.nnnRESULTSnPost-injection reactions, adverse events, medically attended adverse events, and new-onset immune-mediated adverse events were balanced between vaccine groups. Anti-nuclear antibodies, anti-double stranded DNA antibodies, anti-neutrophil cytoplasmic antibodies, and antiphospholipid antibodies were balanced between groups. A transient increase in anti-beta2 glycoprotein 1 IgM was observed in the HBsAg-1018 group but was not associated with a thrombotic event. Serious adverse events and deaths were generally balanced between groups.nnnCONCLUSIONnHBsAg-1018 had a similar safety profile to HBsAg-Eng. With improved immunogenicity and fewer doses over a shorter time, HBsAg-1018 has the potential to provide improved seroprotection and a significant public health benefit to adults 18u202fyears of age or older.

SD-101 in Combination with Pembrolizumab in Advanced Melanoma: Results of a Phase Ib, Multicenter Study

This multicenter phase I/II clinical trial evaluated intratumoral SD-101, a TLR9 agonist, and low-dose radiation in patients with untreated indolent lymphoma. Twenty-nine enrolled patients received 4 Gy of radiation followed by 5 weekly intratumoral injections of SD-101 at a single tumor site. No treatment-related grade 4 or serious adverse events occurred. Nearly all patients had tumor reduction at their treated site. More importantly, 24 patients had tumor reduction at their nontreated sites, with 5 patients achieving a partial response and one achieving a complete response. Treatment-related increases of CD8+ and CD4+ effector T cells and decreases of T follicular helper and T regulatory cells (Treg) were observed in the tumor microenvironment. Low pretreatment levels of CD4+ Tregs, proliferating CD8+ T cells, and Granzyme B+ CD8+ T cells were associated with favorable outcomes. Intratumoral SD-101 in combination with low-dose radiation is well tolerated and results in regression of both treated and untreated sites of disease.Significance: In situ vaccination with the TLR9 agonist SD-101, along with low-dose radiation, was safe and induced systemic responses in patients with indolent lymphoma. Low levels of CD4+ Tregs, proliferating CD8+ T cells, and Granzyme B+ CD8+ T cells in the tumor microenvironment predicted favorable response to treatment. Cancer Discov; 8(10); 1258-69. ©2018 AACR. This article is highlighted in the In This Issue feature, p. 1195.

Abstract LB-239: Pharmacodynamic changes confirm the mechanism of action mediating SD-101 efficacy, in combination with pembrolizumab, in a phase 1b/2 study in metastatic melanoma (MEL-01)

PD-1 inhibitors are approved for treating advanced melanoma, but resistance has been observed. This phase Ib trial evaluated intratumoral SD-101, a synthetic CpG oligonucleotide that stimulates Toll-like receptor 9 (TLR9), in combination with pembrolizumab in patients with unresectable or metastatic malignant melanoma. The most common adverse events related to SD-101 were injection-site reactions and transient, mild-to-moderate flu-like symptoms. Among the 9 patients naïve to anti-PD-1 therapy, the overall response rate (ORR) was 78%. The estimated 12-month progression-free survival rate was 88%, and the overall survival rate was 89%. Among 13 patients having prior anti-PD-1 therapy, the ORR was 15%. RNA profiling of tumor biopsies demonstrated increased CD8+ T cells, natural killer cells, cytotoxic cells, dendritic cells, and B cells. The combination of intratumoral SD-101 and pembrolizumab was well tolerated and induced broad immune activation in the tumor microenvironment with durable tumor responses in both peripheral and visceral lesions.Significance: These early data demonstrate that the combination of pembrolizumab with intratumoral SD-101 is well tolerated and can induce immune activation at the tumor site. Combining an intratumoral TLR9 innate immune stimulant with PD-1 blockade can potentially increase clinical efficacy with minimal additional toxicity relative to PD-1 blockade alone. Cancer Discov; 8(10); 1250-7. ©2018 AACR. This article is highlighted in the In This Issue feature, p. 1195.