[The relationship of mental health providers with health insurers; an exploration]

BACKGROUND

In 2020, Zorgverzekeraars Nederland (ZN), the umbrella organization of nine health insurers in The Netherlands. presented a vision of the future of mental health care in the Netherlands in ‘De GGZ in 2025. Vergezicht op de geestelijke gezondheidszorg’ (‘Outlook on mental health care’). This document can be seen as marking the fact that key stakeholders share a common vision on the future of the GGZ in the Netherlands. Contracting care is often difficult. The tension between providing quality and sufficient care and available funding leads to friction. Congruence in vision, goals and practices are important conditions for adequate relationship building. Does the vision document contribute to this?

AIM

To discuss the experiences of mental health care administrators and health insurers in contracting and collaboration.

METHOD

Conducting interviews with both directors of mental health institutions and the strategic (policy) advisors of health insurers. In the approach we used the salience model.

RESULTS

The relationship between mental health care administrators and health insurers is perceived to be distrustful and complex, and has deteriorated slightly in 2021 compared to 2019. Perceived power, legitimacy and urgency affect the relationship. Almost all health insurers are characterized as dominant stakeholders based on the salience model. Both parties are open to improving the relationship, which requires more transparency and mutual understanding.

CONCLUSION

With the supported content of the vision document, there is to some extent shared governance. The change steps (shared innovation) considered desirable will be promoted by partly granting the intended benefits to each other (shared savings).

An evaluation of the safety and immunogenicity of MVC-COV1901: Results of an interim analysis of a phase III, parallel group, randomized, double-blind, active-controlled immunobridging study in Paraguay

BACKGROUND

Data from previous studies of the MVC-COV1901 vaccine, a subunit vaccine against SARS-CoV-2 based on the stable prefusion spike protein (S-2P) adjuvanted with CpG 1018 adjuvant and aluminum hydroxide, suggest that the vaccine is generally safe and elicits a good immune response in healthy adults and adolescents. By comparing with AZD1222, this study adds to the findings from previous trials and further evaluates the breadth of protection offered by MVC-COV1901.

METHODS

In this phase 3, parallel group, randomized, double-blind, active-controlled trial conducted in 2 sites in Paraguay, we assigned adults aged 18-91 years in a 1:1 ratio to receive intramuscular doses of MVC-COV1901 or AZD1222 administered as scheduled in the clinical trial. Serum samples were collected on the day of vaccination and 14 days after the second dose. Primary and secondary safety and immunogenicity endpoints were assessed. In addition, other outcomes investigated were cross-reactive immunity against the Omicron strain and the induction of IgG subclasses.

RESULTS

A total of 1,030 participants underwent randomization. Safety data was derived from this set while primary immunogenicity data involved a per-protocol immunogenicity (PPI) subset including 225 participants. Among the participants, 58% are seropositive at baseline. When compared against AZD1222, MVC-COV1901 exhibited superiority in terms of neutralizing antibody titers and non-inferiority in terms of seroconversion rates. Reactogenicity was generally mild and no serious adverse event was attributable to MVC-COV1901. Both vaccines have a Th1-biased response predominated by the production of IgG1 and IgG3 subclasses. Omicron-neutralizing titers were 44.5 times lower compared to wildtype-neutralizing titers among seronegative individuals at baseline. This fold-reduction was 3.0 times among the seropositive.

CONCLUSION

Safety and immunogenicity data of MVC-COV1901 from the study in Paraguay confirm previous results. The previous infection coupled with vaccination of this vaccine may offer protection against the Omicron strain though its durability is still unknown.

121. Safety, Tolerability, and Pertussis Immunogenicity Findings From a Randomized, Participant-Blinded, Active-Controlled, Dose-Escalating, Phase 1 Trial of a Tetanus/Diphtheria/Pertussis Booster Vaccine (Tdap-1018 CpG Adjuvanted) Compared With Boostrix in Healthy Adults Aged 18 to 22 Years

Background

Bordetella pertussis is a gram-negative bacterium causing the highly contagious respiratory infection pertussis in over 151 000 individuals annually worldwide. A tetanus/diphtheria/pertussis (Tdap) vaccine combined with CpG 1018 adjuvant (Tdap-1018) may induce higher antibody titers than existing aluminum-adjuvanted Tdap vaccines used as a booster in adults.

Methods

In this randomized, active-controlled, participant-blinded, phase 1 trial, healthy adults aged 18 to 22 years received 1 booster injection of Tdap-1018 (with same Tdap composition as in Boostrix and escalating CpG 1018 dose of 1500 µg and 3000 µg) or Boostrix on Day 1. Pertussis immunogenicity evaluations assessed booster response rates (BRRs) for anti-pertussis toxin (anti-PT), anti-filamentous hemagglutinin (anti-FHA), and anti-pertactin (anti-PRN) antibodies, and systems serology at Week 4 post-vaccination. Safety and tolerability were assessed for solicited local and systemic post-injection reactions for 7 days and unsolicited adverse events for 12 weeks after vaccination.

Results

Of the 87 enrolled adult participants, 84 had post-vaccination immunogenicity results. The median age was 19.0 years, 35% were men, and 83% were white. At Week 4, BRRs in the Tdap-1018 3000 µg group were statistically significantly higher (based on lower 95% confidence interval [CI] >0%) than the Boostrix group for anti-PT (difference in BRRs 22.2% [95% CI: 1.5%–42.8%]) and anti-PRN (22.2% [95% CI: 8.2%–40.9%]) antibodies, and similar for anti-FHA (14.8% [95% CI: -2.6%–33.9%]) antibodies (Table). Tdap-1018 1500 µg, Tdap-1018 3000 µg, and Boostrix were generally well tolerated with no observed safety concerns.

Conclusion

In this phase 1 trial, both dose levels of Tdap-1018 were generally well tolerated. Tdap-1018 3000 µg induced statistically significantly higher BRRs than Boostrix for anti-PT and anti-PRN, and a similar response for anti-FHA antibodies.

Disclosures

Robert Janssen, MD, Dynavax Technologies Corporation: employee|Dynavax Technologies Corporation: Stocks/Bonds Tammy Boyce, MEd, Dynavax Technologies Corporation: Employee|Dynavax Technologies Corporation: Stocks/Bonds Fang Xie, PhD, Dynavax Technologies Corporation: Employee|Dynavax Technologies Corporation: Stocks/Bonds Olivier Godeaux, MD, MPH, Dynavax: Advisor/Consultant.

An Immunobridging Study to Evaluate the Neutralizing Antibody Titer in Adults Immunized with Two Doses of Either ChAdOx1-nCov-19 (AstraZeneca) or MVC-COV1901

Rapid development and deployment of vaccines is crucial to control the continuously evolving COVID-19 pandemic. The placebo-controlled phase 3 efficacy trial is still the standard for authorizing vaccines in the majority of the world. However, due to a lack of eligible participants in parts of the world, this has not always been feasible. Recently, the Taiwan Food and Drug Administration, following the consensus of the International Coalition of Medicines Regulatory Authorities (ICMRA), adopted the use of immunobridging studies as acceptable for authorizing COVID-19 vaccines in lieu of efficacy data. Here, we describe a study in which our candidate vaccine, MVC-COV1901, an adjuvanted protein subunit vaccine, has been granted emergency use authorization (EUA) in Taiwan based on a noninferiority immunobridging study. Immunogenicity results from the per protocol immunogenicity (PPI) subset (n = 903) from the MVC-COV1901 phase 2 trial were compared with results from 200 subjects who had received an adenovirus vector vaccine, AstraZeneca ChAdOx nCOV-19 (AZD1222), in a separate study. The lower bound of the 95% confidence interval (CI) of the geometric mean titer (GMT) ratio comparing MVC-COV1901 to AZD1222 was 3.4. The lower bound of the 95% CI of the sero-response rate was 95.5%. Both the GMT ratio and sero-response rate exceeded the criteria established by the Taiwan regulatory authority, leading to EUA approval of MVC-COV1901 in Taiwan.

Safety and immunogenicity of HepB-CpG in women with documented pregnancies post-vaccination: A retrospective chart review

BACKGROUND

There are currently no published data on the use of HepB-CpG (HEPLISAV-B®) during pregnancy or in women with documented pregnancies in the post-vaccination period. We aimed to evaluate data from the clinical development program of HepB-CpG in women who became pregnant during study participation and follow up.

METHODS

We identified all study participants in the HepB-CpG pivotal pre-licensure clinical trials that had documented pregnancies during study follow up. We measured immunogenicity among study participants in the HepB-CpG (Heplisav-B®) arm compared to the HepB-alum (Engerix-B®) arm of the studies by comparing seroprotection rates (SPRs; anti-HBs ≥ 10 mIU/mL) and geometric mean concentrations (GMCs) of anti-HBs, obtained with FDA approved anti-HBsAg antibody assays at prespecified time points up to 28 weeks of follow up. Pregnancy outcomes were ascertained by chart review of extracted medical records of study participants.

RESULTS

We identified 40 documented pregnancies in the HepB-CpG arm and 19 documented pregnancies in the HepB-alum arm. Among subjects with documentation of seroprotection rates, 97.2% (95% CI 85.5-99.9) were seroprotected in the HepB-CpG arm and 66.7% (95% CI 41.0-86.7) were seroprotected in the HepB-alum arm. In the HepB-CpG arm, thirty-six study participants from the pivotal trials had reported pregnancy outcomes, the majority, 21/36 (58%) had a healthy term delivery, with 3/36 (8%) with spontaneous abortions, 1/36 (3%) congenital anomaly, and 2/36 (6%) had preterm birth. In the HepB-alum arm, 10/17 (59%) had healthy term deliveries, with 2/17 (12%) had spontaneous abortions and 1/17 (6%) had congenital anomaly.

CONCLUSIONS

These limited data suggest that HepB-CpG is immunogenic in women who become pregnant after vaccination, and pregnancy outcomes appear to be similar to women who received HepB-alum prior to pregnancy. These results need to be further verified with larger prospective studies with HBV vaccine administration during pregnancy.

Intralesional SD-101 in Combination with Pembrolizumab in Anti-PD-1 Treatment-Naïve Head and Neck Squamous Cell Carcinoma: Results from a Multicenter, Phase II Trial

PURPOSE

To determine whether SD-101, a Toll-like receptor 9 agonist, potentiates the antitumor activity of anti-PD-1 antibodies in patients with anti-PD-1/PD-L1 naïve, recurrent/metastatic head and neck squamous cell carcinoma (HNSCC).

PATIENTS AND METHODS

Patients with PD-1 Ab-naïve HNSCC received either 2 mg SD-101 injected in one to four lesions or 8 mg SD-101 injected into a single lesion weekly × 4 doses then every 3 weeks × 7 doses. Pembrolizumab was administered at 200 mg every 3 weeks.

RESULTS

A total of 28 patients received 2 mg and 23 received 8 mg per injection, respectively. A total of 76% of patients had received prior systemic therapy. Combined positive score was ≥1 to < 20 in 35 patients (70%) and ≥ 20 in 15 patients (30%) of 50 patients with available data. There were 12 patients with grade ≥3 treatment-related adverse events (24%), and no treatment-related deaths. The objective response rate was 24% including 2 complete and 10 partial responses. The median duration of response was 7.0 [95% confidence interval (CI): 2.1-11.1] months. The response rate was higher in human papillomavirus-positive (HPV+) patients (44%, N = 16). Responses were not associated with PD-L1 expression levels or IFNγ-related gene expression at baseline. Responses were observed both in injected (32%) and in noninjected lesions (29%). Progression-free and overall survival at 9 months were 19.0% (95% CI: 9.1-31.7) and 64.7% (95% CI: 45.3-78.7), respectively.

CONCLUSIONS

SD-101 combined with pembrolizumab induced objective responses, especially in HPV+ tumors, which were frequently associated with increased intratumoral inflammation and effector immune cell activity.

A Phase Ib Open-Label, Multicenter Study of Inhaled DV281, a TLR9 Agonist, in Combination with Nivolumab in Patients with Advanced or Metastatic Non-small Cell Lung Cancer

PURPOSE

Although PD-(L)1 inhibitors have shown efficacy in advanced/metastatic non-small cell lung cancer (NSCLC), many patients do not respond to this treatment and more effective combinations with acceptable toxicities are needed. To assess the potential benefit of combining localized innate immune stimulation with checkpoint blockade, the TLR9 agonist DV281 was combined with nivolumab in a phase Ib study.

PATIENTS AND METHODS

Patients after one or two prior lines of systemic therapy were enrolled in a dose-escalation study with a 3+3 design. DV281 was administered via inhalation in five dose cohorts at 1 to 25 mg; nivolumab 240 mg was administered intravenously every 2 weeks. Safety, tolerability, pharmacodynamics, and response to treatment were assessed.

RESULTS

Twenty-six patients with advanced NSCLC enrolled. Baseline programmed death ligand 1 (PD-L1) expression was present in 16 patients (61.5%); 21 (80.7%) had received previous anti-PD-1/PD-L1. Thirteen patients (50%) had stable disease, nine (34.6%) had progressive disease, and four (15.4%) were not evaluable. Median duration of disease control was 124 days. Adverse events were seen in 16 patients (61.5%), mostly grade 1/2 chills, fatigue, flu-like symptoms, diarrhea, and rash; there was only one grade 3 adverse event (dyspnea). Pharmacodynamic assessment, measured by IFN- inducible gene expression, showed target engagement in all dose cohorts. Systemic pharmacodynamic responses plateaued in the 2 highest dose cohorts.

CONCLUSIONS

DV281 with nivolumab was well tolerated with target engagement observed at every dose. Pharmacodynamic advantages at doses above 10 mg were unclear. The long duration of disease control in 50% of patients suggests clinically relevant activity in this population of heavily pretreated patients.

Safety and immunogenicity of a Recombinant Stabilized Prefusion SARS-CoV-2 Spike Protein Vaccine (MVC-COV1901) Adjuvanted with CpG 1018 and Aluminum Hydroxide in healthy adults: A Phase 1, dose-escalation study

BACKGROUND

This was a phase 1, dose-escalation open-label trial to evaluate the safety and immunogenicity of MVC-COV1901, a SARS-CoV-2 S-2P protein vaccine adjuvanted with aluminum hydroxide and CpG 1018.

METHODS

Between September 28 and November 13 2020, 77 participants were screened. Of these, 45 healthy adults from 20 to 49 years of age were to be administered two doses of MVC-COV1901 in doses of 5 μg, 15 μg, or 25 μg of spike protein at 28 days apart. There were 15 participants in each dose group; all were followed for 28 days after the second dose at the time of the interim analysis. Adverse events and laboratory data were recorded for the safety evaluation. Blood samples were collected for humoral, and cellular immune response at various time points. Trial Registration: ClinicalTrials.gov NCT04487210.

FINDINGS

Solicited adverse events were mostly mild and similar. No subject experienced fever. After the second dose, the geometric mean titers (GMTs) for SARS-CoV-2 spike-specific immunoglobulin G were 7178.2, 7746.1, 11,220.6 in the 5 μg, 15 μg, and 25 μg dose groups, respectively. The neutralizing activity were detected in both methods. (Day 43 GMTs, 538.5, 993.1, and 1905.8 for pseudovirus; and 33.3, 76.3, and 167.4 for wild-type virus). The cellular immune response induced by MVC-COV1901 demonstrated substantially higher numbers of IFN-γ- producing cells, suggesting a Th1-skewed immune response.

INTERPRETATION

The MVC-COV1901 vaccine was well tolerated and elicited robust immune responses and is suitable for further development.

FUNDING

Medigen Vaccine Biologics Corporation.

Association of Number of Doses With Hepatitis B Vaccine Series Completion in US Adults

IMPORTANCE

Receipt of hepatitis B virus vaccine is important to prevent infection. However, adherence to the hepatitis B vaccine series among adults at risk of infection has been low.

OBJECTIVE

To assess whether recipients of a 2-dose hepatitis B vaccine with cytosine phosphoguanine adjuvant (HepB-CpG vaccine; Heplisav-B) are more likely to complete their series compared with recipients of a 3-dose vaccine with alum adjuvant (comparator vaccine; Engerix-B [HepB-alum]).

DESIGN, SETTING, AND PARTICIPANTS

This nested cohort study was conducted from August 7 to December 31, 2018, at Kaiser Permanente Southern California, an integrated health care system with a diverse population of approximately 4.6 million members. Adults not receiving dialysis who received a first dose of a hepatitis B vaccine series in family practice or internal medicine departments of 15 Kaiser Permanente Southern California medical centers were followed up through electronic health records for up to 1 year after receipt of the first dose. Data were analyzed from March 16 to September 23, 2020.

EXPOSURES

Receipt of a first dose of the HepB-CpG vaccine (2-dose vaccine) vs receipt of a first dose of the HepB-alum vaccine (3-dose vaccine).

MAIN OUTCOMES AND MEASURES

Series completion within the recommended vaccine schedule plus 3 months (primary outcome) and series completion within 1 year after receipt of the first dose (secondary outcome).

RESULTS

Of 4727 individuals who initiated the HepB-CpG vaccine series and 6161 individuals who initiated the HepB-alum vaccine series included in the study, 2876 (60.8%) and 3789 (61.5%), respectively, were ages 40 to 59 years, 2415 (51.1%) and 3113 (50.5%) were male, and 2364 (50.0%) and 2881 (46.8%) were Hispanic. The vaccine series was completed within the recommended schedule plus 3 months for 2111 (44.7%) individuals who initiated the HepB-CpG vaccine series and 1607 (26.1%) individuals who initiated the HepB-alum vaccine series, and within 1 year for 2858 (60.5%) and 1989 (32.3%) individuals, respectively. The individuals who initiated the HepB-CpG vaccine series were significantly more likely to complete the series (adjusted relative risk, 1.77; 95% CI, 1.68-1.87). Results were consistent across clinical and demographic strata.

CONCLUSIONS AND RELEVANCE

In this study, use of the HepB-CpG vaccine was associated with hepatitis B vaccine series completion, but tailored strategies to increase completion of hepatitis B vaccine series are warranted.

[Rheumatoid arthritis: more than a joint disease]

Rheumatoid arthritis (RA), one of the most common autoimmune disorders, mostly manifests itself as polyarthritis. However, extra-articular organ manifestations can also occur, even though their incidence has decreased substantially due to effective treatment with disease-modifying anti-rheumatic drugs. In this article we describe three patient cases of extra-articular manifestations in RA in the absence of prominent arthritis. The diversity of symptoms in RA can be of interest to different medical specialties who will occasionally encounter them in daily practice.

Recoil-Induced Asymmetry of Nondipole Molecular Frame Photoelectron Angular Distributions in the Hard X-ray Regime

We investigate angular emission distributions of the 1s photoelectrons of N_{2} ionized by linearly polarized synchrotron radiation at hν=40  keV. As expected, nondipole contributions cause a very strong forward-backward asymmetry in the measured emission distributions. In addition, we observe an unexpected asymmetry with respect to the polarization direction, which depends on the direction of the molecular fragmentation. In particular, photoelectrons are predominantly emitted in the direction of the forward nitrogen atom. This observation cannot be explained via asymmetries introduced by the initial bound and final continuum electronic states of the oriented molecule. The present simulations assign this asymmetry to a novel nontrivial effect of the recoil imposed to the nuclei by the fast photoelectrons and high-energy photons, which results in a propensity for the ions to break up along the axis of the recoil momentum. The results are of particular importance for the interpretation of future experiments at x-ray free electron lasers operating in the few tens of keV regime, where such nondipole and recoil effects will be essential.

Photon-Momentum-Induced Molecular Dynamics in Photoionization of N_{2} at hν=40 keV

We investigate K-shell ionization of N_{2} at 40 keV photon energy. Using a cold target recoil ion momentum spectroscopy reaction microscope, we determine the vector momenta of the photoelectron, the Auger electron, and both N^{+} fragments. These fully differential data show that the dissociation process of the N_{2}^{2+} ion is significantly modified not only by the recoil momentum of the photoelectron but also by the photon momentum and the momentum of the emitted Auger electron. We find that the recoil energy introduced by the photon and the photoelectron momentum is partitioned with a ratio of approximately 30∶70 between the Auger electron and fragment ion kinetic energies, respectively. We also observe that the photon momentum induces an additional rotation of the molecular ion.

286. Hepatitis B Vaccine Compliance: Comparing 2-Dose and 3-Dose Vaccines

Background

Less than 1 in 3 US adults who initiated the 3-dose (0, 1, 6 months) hepatitis B vaccine series have completed it. HepB-CpG (Heplisav-B; Dynavax) is a new licensed adjuvanted vaccine that requires only 2 doses (0, 1 month). As part of a cluster study performed at Kaiser Permanente Southern California, we compared compliance with second dose and series completion for HepB-CpG vs. comparator vaccine (Engerix-B; GlaxoSmithKline) recipients.

Methods

The cohort included adults not on dialysis who received their first dose of hepatitis B vaccine in family or internal medicine departments from 8/7/2018 to 2/1/2019. Second dose compliance was assessed for the full cohort, but series completion was assessed for a subset vaccinated from August 7, 2018 to September 30, 2018 to allow at least 6 months’ follow-up. Compliance rates were estimated using the Kaplan Meier method. Adjusted hazard ratios (aHR) were estimated using Cox proportional hazard regression with robust variance to account for within medical center correlation, adjusting for age, race/ethnicity, census block income and education, prior healthcare utilization, and factors that trigger alerts for hepatitis B vaccination (diabetes and testing for sexually transmitted infections).

Results

There were 6500 HepB-CpG and 7733 comparator vaccine recipients (1,442 and 2,604 prior to September 30, 2018). Rates of second dose compliance at 60 days were 32.9% for HepB-CpG and 29.1% for comparator vaccine, and rates of series completion at 210 days were 56.9% and 20.6%. There was no significant difference in second dose compliance (aHR 1.14, 95% CI: 0.91, 1.47), but HepB-CpG recipients were 5 times more likely to complete the series (aHR 5.17; 95% CI: 3.84, 6.98). Second dose compliance and series completion were significantly less likely among Blacks compared with Whites and significantly more likely among Asians, adults ≥60 years compared with those < 30 years, and adults living in census blocks with a median annual income of $40,000–69,000 compared with < $40,000.

Conclusion

Overall, second dose compliance was similar, but series completion was better for HepB-CpG recipients than comparator vaccine recipients, suggesting that the 2-dose vaccine could lead to improvements in coverage and protection against hepatitis B virus.

Disclosures

All authors: No reported disclosures.

Abstract CT224: Phase Ib/II, open label, multicenter study of inhaled DV281, a Toll-like receptor 9 agonist, in combination with nivolumab in patients with advanced or metastatic non small cell lung cancer (NSCLC)

Background and Objectives: DV281 is a synthetic CpG-ODN agonist of TLR9 that stimulates dendritic cells to release IFN-alpha and mature into antigen presenting cells to activate T cell anti-tumor responses. Nivolumab is a PD-1 inhibitor that has demonstrated activity in advanced/metastatic NSCLC. Study DV9- NSC-01 (NCT03326752) is a phase 1b/2 study to assess safety and pharmacodynamic activity of DV281 in combination with nivolumab in patients with advanced or metastatic NSCLC and to determine the recommended dose for expansion.

Methods: Anti-PD-1/L1 experienced or naïve patients were enrolled in 2L or 3L NSCLC in the escalation phase, 3+3 design: 5 dose cohorts, with intra-patient dose escalation between the first 2 monotherapy doses: cohort 1: 1 mg; cohort 2: 1 to 3 mg; cohort 3: 3 to 10 mg; cohort 4: 10 to 15 mg; cohort 5: 15 to 25 mg. Nivolumab was administered at 240 mg Q2w. Safety was primary objective and pharmacodynamic effects including IFN-inducible gene expression were key secondary objective. DV281 is administered via inhalation, first alone, weekly for 2 doses, then 6 doses weekly with nivolumab, followed by a 5 week off period of DV281, while continuing nivolumab, then DV281 with intravenous nivolumab Q2w for an additional 24 weeks.

Preliminary Results from the Escalation phase: 22 patients have been enrolled to date: Cohort (C) 1: 4 patients; C 2: 3 pts; C3: 7 pts; C 4: 7 pts; C 5: 1pt, ongoing. Median age 67 y/o; male 50%; all ECOG PS0-1 (27.3/72.7%); non squamous 15 (68%), squamous 7 (32%); locally advanced 4 (18%), metastatic 18 (82%); PD-L1 expression: positive 12 pts (52%), negative 10 pts (48%); prior lines of therapy - 1 line: 10 pts (45.5%), 2 lines:12 (54.5%). Previous treatment with PD-1/PD-L1 inhibitors: 18 pts (9 as single agent, 9 in combination). Median treatment duration 11.5 weeks (1 to 38). Eighteen patients discontinued DV281: adverse event 2, PD 14, other 2. Safety profile of DV281 alone and combined with nivolumab with a median number of 5 doses (1.0 to 18.0): grade 1/ 2 chills (18%), fatigue (13.6%), flu-like symptoms (4.5%), diarrhea (13.6%) and rash (13.6%); no grade ≥3 DV281/nivolumab treatment related AE; no immune-related AEs. Pharmacodynamic (PD) assessment (IFN-induced genes) shows target engagement in all dose cohorts, with every patient showing evidence of target engagement in cohorts 3 and 4. A dose dependent increase in PD activity appears to begin to plateau at the 15 mg dose.

Conclusions: In this population of heavily pretreated patients, DV281 in monotherapy and in combination with nivolumab was well tolerated. Target engagement was observed at all dose levels. The expansion phase will use a modified dosing schedule, evaluating several groups of patients: non squamous resistant to PD-1/PD-L1 or to EGFR inhibitors; squamous experienced or naïve to anti PD-1/PD-L1.

Citation Format: Edward Garon, Alexander I. Spira, Melissa Johnson, Lyudmila Bazhenova, Joseph Leach, Albert Candia, Robert Coffman, Mary Janatpour, Erick Gamelin, Robert Janssen, Laura Q. Chow. Phase Ib/II, open label, multicenter study of inhaled DV281, a Toll-like receptor 9 agonist, in combination with nivolumab in patients with advanced or metastatic non small cell lung cancer (NSCLC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT224.

Phase 1b/2, open label, multicenter, study of the combination of SD-101 and pembrolizumab in patients with advanced melanoma who are naïve to anti-PD-1 therapy

9534

Background: SD-101 is a synthetic CpG TLR9 agonist. Pembrolizumab is a PD-1 inhibitor. SYNERGY-001/KEYNOTE-184 assesses the safety and preliminary efficacy of the combination of SD-101 and pembrolizumab in patients naïve to anti-PD-1/L1 therapy with unresectable stage IIIC-IV melanoma. Methods: SD-101 was evaluated as 2 mg/lesion injected into 1 to 4 lesions and 8 mg/lesion in 1 lesion as 4 weekly doses followed by 7 doses Q3W. Pembrolizumab was administered as 200 mg IV Q3W. CT scans were performed every 9 weeks. Responses were assessed per investigator using RECIST v1.1. Responses and post-hoc Kaplan-Meier analyses of PFS in the ITT population were compared for patients who received 2 mg/lesion with 8 mg/lesion. Results: 86 patients (2 mg: N = 45; 8 mg: N = 41) have been enrolled with similar baseline characteristics: median age = 66 years; male = 67%; ECOG stage 0 = 67%; disease stage: IIIC = 21%; IVM1a/b = 50%; IVM1c = 28%; LDH ≤ ULN = 71%; treatment naïve = 73%. Median follow up to date is 8.1 months in 2 mg group and 8.3 months in 8 mg group. SD-101 safety profile comprises flu-like symptoms with most frequent grade ≥3 SD-101-related AEs of headache (7%), fatigue (7%), malaise (5%), myalgia (4%), and chills (4%). Immune-related AEs were reported in 19%. ORR in 2 mg group = 71% (95% CI: 57, 82) (CR: 13%) and in 8 mg group = 49% (95% CI: 33, 65) (CR: 7%) with responses in both injected and non-injected lesions, including visceral. DOR = not reached (NR) in either group. ORR by baseline PD-L1 expression in 62 patients, 53% of whom were PD-L1 positive: 2 mg = 80%/79% (PD-L1 positive/negative); 8 mg = 62%/40% (PD-L1 positive/negative). PFS was higher in 2 mg group with median PFS in 2 mg = NR (95% CI: Not estimable [NE], NE) and in 8 mg = 10.4 months (95% CI: 4.2, NE), HR = 0.45 (95% CI: 0.21, 0.98), p = 0.036. 6 month PFS rate in 2 mg = 81% and in 8 mg = 60%. 6 month OS rate in 2 mg = 98% and in 8 mg = 92%. Conclusions: The TLR9 innate immune stimulant, SD-101, in combination with pembrolizumab has been well-tolerated, and is showing promising high response rates and PFS, regardless of PD-L1 expression, particularly in patients who received 2 mg SD-101. Clinical trial information: NCT02521870.

Phase 1b/2, open label, multicenter, study of the combination of SD-101 and pembrolizumab in patients with advanced/metastatic melanoma resistant to anti-PD-1/PD-L1 therapy

9555

Background: SD-101 is a synthetic CpG-ODN agonist of TLR9 that stimulates dendritic cells to release IFN-alpha and mature into antigen presenting cells - activating T cell anti-tumor responses. Pembrolizumab has demonstrated activity in melanoma. SYNERGY-001/KEYNOTE-184 study assesses the safety and preliminary efficacy of the combination of intratumoral SD-101 and intravenous pembrolizumab in PD1/PDL 1 resistant unresectable stage IIIC- IV melanoma. A prior phase 2 study with SD-101 at 8 mg per injection resulted in a 21.4% ORR in this population (Abstract 3781, ESMO 2018). We report preliminary data in this ongoing phase 2 trial evaluating efficacy at a lower SD-101 dose of 2 mg per injection. Methods: PD1/PDL 1 resistant melanoma patients received 2 mg of SD-101 intratumorally per lesion in 1-4 lesions (weekly x 4 doses followed by Q3W x 7). Pembrolizumab was administered at a dose of 200 mg intravenously Q3W. Scans were performed Q9W. Responses were assessed per RECIST v1.1. Results: 23 patients have been enrolled with baseline characteristics: median age 65 years; male: 77%; stage at screening: IIIC = 26%; IV = 57%, unknown = 17%; LDH > ULN: 36%. Lines of prior therapy: 1: 52%; 2: 22%; > 2: 26%. Prior anti CTL-A4 therapy: 39%. Best overall response on prior antiPD-1/PD-L1: PD: 88%, PR/CR: 8%, SD: 4%. Safety: Grade ≥3 treatment-related AEs: pneumonia and constipation (8%). No immune-related AEs reported. 2 non-treatment related SAEs reported from 2 patients: pneumonia and intussusception. 4 patients discontinued treatment early: 1 post SAE, per patient’s request, 3 due to PD. 1 patient died due to malignant pleural effusion after 1 dose of SD 101 and Pembrolizumab. No treatment related deaths. Efficacy: Mean duration on treatment: 39 days (1 - 169). mITT population: six patients at time of first CT scan at day 64: PR: 1, SD: 1, PD:3; non-evaluable: 1. 17 patients on study have not yet had first CT scan. Conclusions: The TLR9 innate immune stimulant, SD-101, in combination with pembrolizumab is well tolerated. Mature efficacy data, with additional first and second follow-up CT scans, will be presented at the meeting. Clinical trial information: NCT02521870.

Phase 1b/2, open label, multicenter study of intratumoral SD-101 in combination with pembrolizumab in anti-PD-1 treatment naïve patients with recurrent or metastatic head and neck squamous cell carcinoma (HNSCC)

6039

Background: SD-101, a synthetic CpG-ODN agonist of TLR9, stimulates dendritic cells to release IFN-alpha and mature into antigen presenting cells - activating T cell anti-tumor responses. Pembrolizumab has demonstrated activity in HNSCC. Study DV3-MEL-01 (NCT02521870) assesses safety and efficacy of SD-101 in combination with pembrolizumab in patients with recurrent/metastatic HNSCC. We have previously reported a 27.3% ORR in 22 patients receiving 8 mg SD-101/injection in the modified ITT after at least 2 CT scans due to late responses (Abstract 3560, ESMO 2018). Higher efficacy at a lower SD-101 dose, 2 mg/injection, has been reported in advanced melanoma patients (LBA 45, ESMO 2018). Consequently, this dose is now being assessed in HNSCC. We report preliminary data with the 2 mg/injection dose in 23 patients in mITT at the first CT scan. Methods: Anti-PD-1/PD-L1 naïve patients received 2 mg SD-101 intratumorally in 1 - 4 lesions (weekly x 4 doses then Q3W x 7 doses). Pembrolizumab is was administered IV at 200 mg Q3W. Responses were assessed per RECIST v1.1. Results: 28 patients enrolled: median age 63 y/o, male 68%; ECOG PS 0-1 (18%/82%); mean prior lines of systemic therapy 1 (0-3); mean treatment duration 70 days (1-253). Primary tumors: 19 (68%) oropharyngeal; 3 (10%) laryngeal; 2 (7%) hypopharyngeal; 4 (14%) unknown. Mean number of target lesions: 1.82 (1 to 5). HPV status: 7 (25%) +, 9 (32%) -, 12 (43%) unknown. 18 (64 %) discontinued treatment: 12 (42%) due to PD, 4 (16%) deaths, 1 (3%) consent withdrawn, 1 (3%) went to hospice. Mean follow up 2.70 months. Safety: 16 non-treatment-related SAEs in 9 patients. 2 treatment-related Grade ≥3 AEs: sepsis (4%) and lymphopenia (4% ). No treatment-related deaths. Efficacy: 23 patients in the mITT population with first CT scan at day 64: ORR: CR: 2, PR: 3 (22%); SD: 6 (26%), PD: 7 (30%), non-evaluable: 5 (22%). Disease control rate (48%). 5 patients on study have not had a CT scan. Conclusions: SD-101 with Pembrolizumab shows early promising data and is well tolerated. Additional follow-up scans from both dose cohorts are being evaluated and will be presented. Clinical trial information: NCT02521870.

2287. Recently Approved HEPLISAV-B(R) [Hepatitis B Vaccine (Recombinant), Adjuvanted] Shows a Higher Proportion of Subjects Achieving Seroprotection With a More Consistent Immune Response Compared With Engerix-B(R) [Hepatitis B Vaccine (Recombinant)] in Three Comparative Trials

Background

HEPLISAV-B^® [hepatitis B vaccine (recombinant), adjuvanted] uses a cytidine phospho-guanosine (CpG) oligonucleotide or “1018,” a Toll-like receptor 9 agonist, as an adjuvant. Engerix-B^® [hepatitis B vaccine (recombinant)], as well as other hepatitis B vaccines, use alum. HEPLISAV-B, a 2-dose vaccine given at Weeks 0 and 4, was recently approved for use in adults ≥18 years for the prevention of hepatitis B. Approval of HEPLISAV-B was based on three pivotal phase 3 noninferiority trials, comparing it with Engerix-B, a 3-dose vaccine given at Day 0, Day 30, and 6 months. Immunogenicity and safety results for these trials, HBV-10, HBV-16 and HBV-23, have been published previously; the safety of HEPLISAV-B was generally similar to Engerix-B.

Methods

The 3 randomized trials were observer-blinded and collectively included subjects aged 18–70 years. Immunogenicity analysis based on antibody against hepatitis B surface antigen (anti-HBs) levels were based on the per-protocol analysis. Presented here are reverse cumulative frequency plots of anti-HBs serum concentrations for the 3 trials.

Results

Across the trials, reverse cumulative frequency plots of anti-HBs concentrations showed a higher proportion (>90%) of HEPLISAV-B subjects developed a seroprotective antibody level (anti-HBs levels ≥10 mIU/mL) compared with Engerix-B subjects (80% to ~90%). A higher proportion of HEPLISAV-B subjects had anti-HBs levels between 10 mIU/mL and 1,000 mIU/mL. While a higher proportion of Engerix-B subjects had anti-HBs levels >1,000 mIU/mL, a significantly higher proportion of Engerix-B subjects did not develop seroprotective antibody levels. The response curves indicate a more consistent immune response with a higher percentage of subjects achieving seroprotection with less variability for HEPLISAV-B compared with Engerix-B, which showed a more variable response and fewer subjects achieving seroprotection.

Conclusion

HEPLISAV-B, using a CpG adjuvant, results in a higher percentage of persons achieving seroprotection and produces a more uniform and consistent induction of protective antibody levels than Engerix-B, an alum-adjuvanted vaccine.

Disclosures

R. N. Hyer, Dynavax Technologies Corporation: Employee and Shareholder, Salary and Stock options. R. Janssen, Dynavax Technologies Corporation: Employee and Shareholder, Salary and Stock options.

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

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 CT139: Durability of responses to the combination of SD-101 and pembrolizumab in advanced metastatic melanoma: Results of a phase Ib, multicenter study

Background: This phase 1b trial evaluates the safety and antitumor efficacy of the combination of SD-101, a synthetic CpG-oligonucleotide that stimulates Toll-like receptor 9 (TLR9), and pembrolizumab in patients with recurrent Stage IIIC/IV malignant melanoma.

Methods: Dose escalation of SD-101 used a modified 3+3 design. SD-101 was injected in a single tumor lesion (weekly x 4 doses then every 3 weeks x 7 doses over 6 months) at 1, 2, 4, or 8 mg and pembrolizumab was administered intravenously at 200 mg every 3 weeks up to 2 years. Tumor responses were assessed per investigator using RECIST v1.1 taking into account both injected and non-injected lesions.

Results: Of the 22 patients, 9 were naïve to anti-PD-1/L1 therapy at baseline and 13 had progressive disease while receiving prior anti-PD-1/L1 therapy. Treatment was well tolerated with no Grade 3 or higher treatment-related AEs in longer term follow up. Among the 9 patients who were anti-PD-1/L1 naïve, best objective responses were CR: 2, PR: 5, PD: 1, not evaluated [NE]: 1. Median PFS, duration of response, and OS have not been reached. Estimated 12 month PFS was 88% and OS was 89%. After a median of 18 months of follow-up, 86% of responses were ongoing. One patient with a PR developed progressive disease after 20 months of treatment. Among patients who had received prior anti-PD-1/L1 therapy, best objective responses were PR: 2, SD: 5, PD: 5, NE: 1. One patient with stable disease and 1 patient with a PR continued on combination therapy without progression for at least 10.5 months. The other 10 patients developed progressive disease ranging from 1.5 to 8 months after enrollment. Percent change in tumor size from baseline in injected and non-injected lesions will also be presented.

Conclusion: These early results suggest that combining an intratumoral TLR9 innate immune stimulant with PD-1 blockade can potentially provide more clinical responses that are meaningfully durable than PD-1 blockade alone based on historical data.

Citation Format: Antoni Ribas, Theresa Medina, Shivaani Kummar, Asim Amin, Joseph J. Drabick, Minal Barve, Gregory Daniels, Deborah L. Wong, Emmett V. Schmidt, Abraham C. Leung, Robert Janssen. Durability of responses to the combination of SD-101 and pembrolizumab in advanced metastatic melanoma: Results of a phase Ib, multicenter study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr CT139.

Abstract CT098: Phase Ib/II, open label, multicenter study of intratumoral SD-101 in combination with pembrolizumab in anti-PD-1 treatment naïve patients with recurrent or metastatic head and neck squamous cell carcinoma (HNSCC)

Background and Objectives: SD-101 is a synthetic CpG-ODN agonist of TLR9 that stimulates dendritic cells to release IFN-alpha and mature into antigen presenting cells to activate T cell anti-tumor responses. Pembrolizumab is a PD-1 inhibitor that has demonstrated activity in HNSCC with ORR of 14%. Study DV3-MEL-01 (NCT02521870) assesses the safety and preliminary efficacy of SD-101 in combination with pembrolizumab in patients with recurrent or metastatic HNSCC.

Methods: In phase 2 expansion cohort for anti-PD-1 treatment naïve HNSCC patients, SD-101 was injected in a single tumor lesion (weekly x 4 doses then every 3 weeks x 7 doses) at 8 mg and pembrolizumab was administered intravenously at 200 mg every 3 weeks. Responses are assessed per investigator using RECIST v1.1/irRECIST.

Preliminary Data and Results: 16 anti-PD-1 treatment naïve HNSCC patients are enrolled to date: median age 65 y/o, male 94%, ECOG PS1 63%, median prior lines of therapy 1. SD-101 safety profile consists of flu-like symptoms and injection-site reactions. Grade≥3 treatment-related AEs observed to date included influenza-like symptoms, myalgia, headache, injection site pain and swelling, and fatigue with each of the toxicities occurring in 1 patient (6.7%). No increase in frequency of known pembrolizumab immune-related AEs has been observed to date. ORR in evaluable pts (n=10) was 40% (4 PRs; 1 SD, 5 PDs with 1 still on treatment). The duration of response will be characterized when follow-up data become more mature.

Conclusions: In anti-PD-1 treatment naïve HNSCC patients, SD-101 in combination with pembrolizumab showed a promising response rate and has been well tolerated. Full accrual of subjects in this cohort is ongoing.

Citation Format: Ezra Cohen, Sarwan Bishnoi, Douglas E. Laux, Deborah Wong, Asim Amin, Lisle Nabell, Emmett V. Schmidt, Biao Xing, Abraham C. Leung, Robert Janssen. Phase Ib/II, open label, multicenter study of intratumoral SD-101 in combination with pembrolizumab in anti-PD-1 treatment naïve patients with recurrent or metastatic head and neck squamous cell carcinoma (HNSCC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr CT098.

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)

Introduction: SD-101 is a synthetic CpG oligonucleotide agonist of Toll-like receptor 9. SD-101 stimulates dendritic cells to release interferon-alpha and mature into antigen presenting cells that effectively activate T cell responses. Pembrolizumab is a PD-1 inhibitor that has been approved for the treatment of multiple tumors including metastatic melanoma. In mouse tumor models, SD-101 synergizes with anti-PD-1 inducing substantial infiltration of tumor-reactive T cells and durable, complete responses in all treated animals. The MEL-01 trial assesses the safety and preliminary efficacy of SD-101 in combination with pembrolizumab in stage IIIC-IV melanoma. Previously presented clinical data suggest enhanced efficacy for this combination. Biomarker data from the MEL-01 trial support the mechanism of action of SD-101.

Methods: The dose escalation phase of this trial is a modified 3 + 3 design with 4 dose levels of SD-101 (1, 2, 4, and 8 mg) in combination with pembrolizumab. SD-101 is injected into a single tumor lesion qw X 4 followed by q3w X 7. Pembrolizumab is dosed at 200 mg IV q3w. Specimens for biomarker analyses included biopsies of the injected tumor and peripheral blood, and were taken before and after treatment (Days 29, 85 and 169). Biopsies were analyzed by multiplexed immunohistochemistry and Nanostring to evaluate the immunophenotype of the tumor environment. Peripheral blood collected immediately before and 24 hours after dosing was analyzed by qPCR with a panel of interferon (IFN) responsive genes to confirm target engagement. Tumor responses were assessed using RECIST v1.1.

Results: IFN signature profiling in blood indicated that SD-101 engages its target in a dose-dependent manner. In tumor biopsies taken after the fourth intratumoral injection, an elevated IFN signature was also observed, confirming persistent local immune activation. Nanostring assessments demonstrated increases in multiple immune cell types in tumors in a subset of patients. In particular, an increase in Th1 responses and a decrease in Th2 responses were found, a shift which is consistent the mechanism of action of SD-101. Immunophenotypic signatures generally correlated with tumor response and were greater in patients naïve to PD-1 treatment compared to patients who previously progressed on PD-1 treatment. Signals for immune suppression generally showed an inverse correlation with clinical response. An elevated CD8 profile was detected by Nanostring and confirmed by immunohistochemistry showing increased CD8+ T cell infiltration in tumors.

Conclusions: Biomarker assessments of the tumor microenvironment in melanoma patients receiving SD-101 and pembrolizumab demonstrate an immunophenotype with CD8 infiltration and a Th1 driven immune response consistent with the mechanism of action and anti-tumor activity of this combination.

Citation Format: Albert Candia, Cristiana Guiducci, Robert L. Coffman, Graeme Currie, Abraham Leung, Robert Janssen, Shivaani Kummar, Sanjiv Agarwala, John Nemunaitis, Rene Gonzalez, Joseph Drabick, Antoni Ribas. 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) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-239. doi:10.1158/1538-7445.AM2017-LB-239

Phase 1b/2, open label, multicenter, study of intratumoral SD-101 in combination with pembrolizumab in anti-PD1 naïve & experienced metastatic melanoma patients

9550

Background: SD-101 is a synthetic CpG-ODN agonist of TLR 9 that stimulates dendritic cells to release IFN-alpha and mature into antigen presenting cells to activate T cell anti-tumor responses. Pembro is a PD-1 inhibitor approved for the treatment of metastatic melanoma. This study, MEL-01 (NCT02521870), assesses the safety and preliminary efficacy of SD-101 in combination with pembro in stage IIIC-IV melanoma. Methods: A modified 3+3 design was used for SD-101 dose escalation of 1, 2, 4, and 8 mg injected in a single tumor lesion Q1W x 4 then Q3W x 7 in combination with pembro (200 mg IV Q3W). Tumor responses were assessed per investigator using RECIST v1.1. Results: In phase Ib, 22 pts were enrolled: median age 64 y/o, male 68%, white 82%, Stage IV/IIIc 86%/14%, LDH > 1 ULN 27%, ≥ 3 prior lines therapy 36%, anti-PD-1 naïve (n = 9) and experienced (n = 13). There has been no dose limiting toxicity (DLT) to date. The most common (≥20%) treatment-related AEs (TRAEs) were transient low-grade fatigue, myalgia, headache, chills and injection site reactions. Grade ≥ 3 TRAEs were observed in 59.1% pts (most common: myalgia 13.6% and injection site pain 13.6%). Immune-related AEs occurred in 2 pts. One had a G2 pneumonitis on Day 23 resulting in drug withdrawal and the other G3 hypophysitis (85 days after last treatment). No deaths occurred. Responses were observed at all doses in PD-1 inhibitor naïve pts, both at the injected and non-injected lesions. A response was seen at the 8 mg dose in PD-1 inhibitor experienced pts. With median f/u of 97 days (max 382), the ORR was 66.7% in the PD-1 inhibitor naïve patients with best overall response of CR 22.2% (n = 2), PR 44.4% (n = 4), SD 11.1% (n = 1), PD 11.1% (n = 1), and NE 11.1% (n = 1). In the PD-1 inhibitor experienced pts: PR 7.7% (n = 1) and SD 38.5% (n = 5). Conclusions: The combination of SD-101 and pembro was well tolerated and demonstrates no worsening of the expected toxicities of each of the individual monotherapies. These interim data support enhanced activity of adding SD-101 to pembro in anti-PD-1 naive metastatic melanoma as well as potential activity in anti-PD-1 experienced pts. Additional follow up data through May 15, 2017 will be presented. Clinical trial information: NCT02521870.

Abstract CT047: SD-101, a novel intratumoral class C CpG-ODN, given with low-dose radiation in patients with untreated low-grade B-cell lymphoma: interim results of a phase I trial

Prior studies have shown preliminary clinical efficacy in combining CPG-ODN with radiation therapy (XRT) to patients with indolent B-cell lymphoma. We report Phase 1 data of combination XRT and SD-101, a synthetic class C CPG-ODN, selected for strong induction of type I interferon.

Methods: This dose-escalation Phase I trial (3+3 design) enrolled patients with untreated indolent B-cell lymphoma. The primary endpoints were safety and alpha-interferon-gene induction. Secondary endpoints included efficacy assessment using Cheson (1999) criteria and quantification of changes in tumor-infiltrating lymphocytes. Patients had a single lesion treated with XRT (2 Gy daily X 2 days) followed by weekly intratumoral SD-101 × 5 doses. Pharmacodynamic assessment included flow cytometry assessment of T-cell infiltrates in a FNA sample of the treated tumor and RT-PCR RNA assay of whole blood to assess induction of alpha-interferon genes. Efficacy assessment included imaging (CT at 3, 6, and every 6 months thereafter).

Results: As of 23 Dec 2015, 13 patients total were enrolled and treated with SD-101 doses of 1, 2, 4 or 8 mg/dose. There were no dose limiting toxicities. Twelve patients received all planned doses of XRT and SD-101. One patient (8 mg) withdrew consent for treatment after receiving 1 SD-101 dose due to Grade 2 confusion and flu-like symptoms. The most common adverse events (AEs) (decreasing frequency) were chills, malaise, myalgia, fatigue, headache, pyrexia, and nausea, typically resolving within 48 hours. One serious AE occurred (Grade 3 Pulmonary Embolism (4 mg)) which was incidental and asymptomatic. There were 2 dose delays due to an AE (Grade 3 neutropenia) in the same patient (8 mg) that resolved without treatment. The other AE was Grade 3 malaise reported in 2 patients (8 mg). At study Day 90, a reduction of the product of diameters in treated tumors occurred in 12 patients (median -45.3%; range [-87, +100]) and in non-treated tumors occurred in 11 patients (median -8.1%; range [-48, +45]). An induction of alpha-interferon genes occurred at all dose levels with similar level of induction. At the treated site, regulatory T-cells (T Regs) were reduced in 8 of 10 patients (average decrease 22.3 + 9.5%) at Day 8. There was an average reduction of 83.3 + 9.9% in follicular T helper cells (Tfh) at Day 8 (n = 9 with baseline Tfh).

Conclusions: SD-101 combined with radiation therapy showed preliminary abscopal anti-tumor activity and was well tolerated. A maximum tolerated dose has not yet been reached at the doses explored. Target engagement of the TLR-9 receptor (induction of interferon-alpha genes) was observed across all dose groups. A decrease in the proportion of T Regs and Tfh cells suggests modulation of their inhibitory effects and tumor growth promoting effects, respectively. The study is currently enrolling 2 expansion cohorts at 1 mg and 8 mg.

Citation Format: Ronald Levy, Nancy Bartlett, Jonathan Friedberg, Patrick Reagan, Leo Gordon, Craig Bergman, Robert Coffman, Robert Janssen, Albert Candia, Michael Khodadoust, Matthew Frank, Steven Long, Debra Czerwinski, Michael Chu, Holbrook Kohrt. SD-101, a novel intratumoral class C CpG-ODN, given with low-dose radiation in patients with untreated low-grade B-cell lymphoma: interim results of a phase I trial. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr CT047.

[Two sisters with lung emphysema]

BACKGROUND

α1-antitrypsin is an antiprotease that is mainly produced in the liver; it plays a crucial role in the protection of lung parenchyma against the destructive effects of proteases. Mutations in the α1-antitrypsin gene can cause α1-antitrypsin deficiency. Individuals homozygous for the Z-genotype have drastically lowered serum α1-antitrypsine concentrations and often develop lung emphysema at an early age.

CASE DESCRIPTION

A 38-year-old woman and her 43-year-old sister both developed lung emphysema at an early age; this could be attributed to severe α1-antitrypsin deficiency. The only treatment for this condition is α1-antitrypsin supplement therapy, but this therapy is not reimbursed by health insurance companies in the Netherlands.

CONCLUSION

α1-antitrypsin deficiency is a relatively rare cause of lung emphysema and can be seen as an orphan phenotype of chronic obstructive pulmonary disease (COPD). We appeal for reconsideration of coverage of α1-antitrypsine supplement therapy by basic health insurance in the Netherlands, on the basis of a recent randomised placebo-controlled study in which the protective effect of this therapy on progressive emphysema was demonstrated by CT lung densitometry.

Single nucleotide polymorphisms in immune response genes in acute Q fever cases with differences in self-reported symptoms

Genes involved in human immune response are well recognized to influence the clinical course of infection. The association of host genetics with susceptibility to and severity of clinical symptoms in acute Q fever was investigated. Single nucleotide polymorphisms (SNPs) in the IFNG (rs2430561/rs1861493), STAT1 (rs1914408), and VDR (rs2228570) genes were determined in 85 patients from the 2007 Dutch acute Q fever outbreak, and a symptom score was calculated. IFNG rs1861493 showed a significant association with the symptom score; IFNG rs2430561 showed a similar trend. These SNPs were then used to reproduce results in a 2009 outbreak population (n = 123). The median symptom score differed significantly in both populations: 2 versus 7. The significant association of IFNG rs1861493 with symptom score in the first population was not reproduced in the second population. We hypothesize that individuals in the second outbreak were exposed to a higher Coxiella burnetii dose compared to the first, which overruled the protection conferred by the A-allele of IFNG rs1861493 in the first population.

Vitamin D-binding protein haplotype is associated with hospitalization for RSV bronchiolitis

BACKGROUND

Between 75 000 and 125 000 U.S. infants are hospitalized for respiratory syncytial virus (RSV) bronchiolitis every year. Up to half will be diagnosed with asthma in later childhood. Vitamin D deficiency has been associated with susceptibility to asthma and respiratory infections. Measured vitamin D is largely bound to vitamin D-binding protein (VDBP); VDBP levels are influenced by its gene (GC) haplotype.

OBJECTIVE

We assessed the relationship between polymorphisms rs7041 and rs4588, which define haplotypes GC1s, GC1f, and GC2, and RSV bronchiolitis susceptibility and subsequent asthma.

METHODS

We retrospectively recruited 198 otherwise healthy children (93% White) hospitalized for severe RSV bronchiolitis in Boston and 333 parents into a follow-up study to assess asthma diagnosis. Data were analysed using family-based genetic association tests. We independently validated our results in 465 White children hospitalized with RSV bronchiolitis and 930 White population controls from the Netherlands.

RESULTS

The rs7041_C allele (denoting haplotype GC1s) was overtransmitted (P = 0.02, additive model) in the entire Boston cohort, in Whites (P = 0.03), and especially in children subsequently diagnosed with asthma (P = 0.006). The GC1f haplotype was undertransmitted in the asthma subgroups (all races and White, both P < 0.05). The rs7041_C allele was also more frequent in the RSV bronchiolitis group compared with controls (OR 1.12, 95% CI 1.02, 1.4, P = 0.03) in the Netherlands, especially in mechanically ventilated patients (P = 0.009).

CONCLUSION AND CLINICAL RELEVANCE

GC1s haplotype carriage may increase the risk of RSV bronchiolitis in infancy and subsequent asthma development. The GC1s haplotype is associated with higher VDBP levels, resulting in less freely available vitamin D.

KEY MESSAGES

Vitamin D-binding protein (VDBP) haplotypes influence free vitamin D levels. We report an association between a VDBP haplotype and hospitalization for RSV bronchiolitis in infancy in two independent cohorts.

Reaction-Diffusion Dissipative Systems—Detailed Stability Analysis-Pattern of Growth and Effect of Inhomogenity

A detailed stability analysis of the one dimensional steady state solutions for the Brusselator model under the conditions of diffusion of initial (non-autocatalytic) components has been performed both for zero flux as well as fixed boundary conditions. In addition to subcritical as well as supercritical bifurcations, situations have been observed where all solution branches at a bifurcation point are unstable. A case of degenerate steady state bifurcation (2 solutions emanating from the same bifurcation point) has also been noticed. A transient simulation of the system in growth reveals the importance of growth rate on the pattern selection process and suggests that the selection of branches at a bifurcation point may be influenced by perturbations/ fluctuations. It also indicates that a stability analysis of the bifurcation diagram alone cannot decide the state of the system in a transient process, and under certain situations complex behavior may be observed at limit points.

Numerical calculations on coupled cells indicate that a heterogenity in the system can introduce multiple (two) time scales in the system. As the ratio of time scales increases, aperiodic or irregular oscillations are observed for the 'fast' variable. A combination of cells with one cell in a steady-state mode and the other in a periodic motion results in a combined motion of the entire system. For a distributed parameter system, a heterogenity can cause development of sharp local concentration gradients, alter the stability properties of steady state as well as periodic solutions and can cause partitioning of the system.

Imperfect Bifurcations and Spatial Structures in Dissipative Systems

One-dimensional reaction-diffusion equations associated with the trimolecular model of Prigogine and Lefever ("Brusselator") are analyzed. A physical description of possibilities of keeping con-centrations of initial components constant is discussed. It is shown that the problem considering diffusion of initial components gives rise to an imperfect bifurcation problem. The diffusion equa-tions have been solved numerically by a continuation procedure for the fixed and zero flux boundary conditions. The analysis indicates that the models including diffusion of all reacting components do not admit an occurence of trivial solutions. These models, as a result, also exclude the pos-sibility of primary bifurcations. The models which consider diffusion of the initial components suppress the number of possible solutions of governing equations. These models may also predict both symmetric and asymmetric states. Apparently this type of models is more suitable for predic-tion of patterns of spatial organization in growth. Since the number of possible profiles is strongly reduced this principle may lead to a more deterministic way of an evolution process. Symmetric profiles occuring on an isola cannot be reached by an evolution process unless a large perturbation is imposed on the system.

Technical strategies to improve tissue engineering of cartilage-carrier-constructs

Technical aspects play an important role in tissue engineering. Especially an improved design of bioreactors is crucial for cultivation of artificial three-dimensional tissues in vitro. Here formation of cartilage-carrier-constructs is used to demonstrate that the quality of the tissue can be significantly improved by using optimized culture conditions (oxygen concentration, growth factor combination) as well as special bioreactor techniques to induce fluid-dynamic, hydrostatic or mechanical load during generation of cartilage.

Interactive spatial tools for the design of regional adaptation strategies

Regional adaptation strategies are plans that consist of feasible measures to shift a region towards a system that is flexible and robust for future climate changes. They apply to regional impacts of climate change and are imbedded in broader planning. Multiple adaptation frameworks and guidelines exist that describe the development stages of regional adaptation strategies. Spatial information plays a key role in the design of adaptation measures as both the effects of climate change as well as many adaptation measures have spatial impacts. Interactive spatial support tools such as drawing, simulation and evaluation tools can assist the development process. This paper presents how to connect tasks derived from the actual development stages to spatial support tools in an interactive multi-stakeholder context. This link helps to decide what spatial tools are suited to support which stages in the development process of regional adaptation strategies. The practical implication of the link is illustrated for three case study workshops in the Netherlands. The regional planning workshops combine expertise from both scientists and stakeholders with an interactive mapping device. This approach triggered participants to share their expertise and stimulated integration of knowledge.

Psychometric evaluation of a Dutch version of the Mini PAS-ADD for assessing psychiatric disorders in adults with different levels of intellectual disability

BACKGROUND

People with intellectual disabilities (ID) have an increased vulnerability to develop psychiatric problems. Moreover, the early recognition and the accurate diagnosis of psychiatric disorders in the population of persons with ID are challenging.

METHOD

A Dutch version of the Mini PAS-ADD, which is a screening instrument for identification of mental health problems in people with ID, was evaluated in terms of internal consistency, interinformant reliability, item grouping and criterion validity based on a large-scale random sample (n = 377) and a clinical sample (n = 99) of adults with ID.

RESULTS

The Dutch version of the Mini PAS-ADD showed moderate internal consistency, and moderate concordance among informants. Both aspects of the reliability were comparable for different levels of ID. A factor analysis largely confirmed the scale structure. Concurrent validity with the Reiss Screen for Maladaptive Behavior was high for the Depression, Psychosis and Autism scale. The outcome of the criterion-validity analysis indicated high specificity. The sensitivity for specific psychiatric disorders by the corresponding scales was moderate, but the general sensitivity for the presence of psychopathology on the basis of any of the scales was satisfying.

CONCLUSIONS

The present research reconfirmed the use of the Mini PAS-ADD as a primary screening device for the identification of mental health problems among people with ID.

Confirmation of an association between single nucleotide polymorphisms in the VDR gene with respiratory syncytial virus related disease in South African children

Respiratory syncytial virus is a leading cause of lower respiratory tract infection in infants. Disease severity has been linked to host immune responses and polymorphisms in genes associated with innate immunity. A large-scale genetics study of single nucleotide polymorphisms (SNPs) in children in the Netherlands identified SNPs in the vitamin D receptor (VDR) and JUN genes which have a strong association with an increased risk of developing bronchiolitis following the first respiratory syncytial virus (RSV) infection. The Toll-like receptor 4 (TLR4) gene has two SNPs which have been associated previously with RSV disease severity in various populations. The aim of this study was to determine if these SNPs may be associated with RSV disease in African children in South Africa. RSV patient (n = 296) and control (n = 113) groups were established (median ages: 3 and 3.5 months) and DNA extracted from the collected specimens. Real-time polymerase chain reaction using hydrolysis probes was used to screen for SNPs in the VDR (Thr1Meth; rs10735810), TLR4 (Asp299Gly; rs4986790 and Thr399Ile; rs4986791) and JUN (c.750G/A; rs11688) genes. Carriers of the VDR (Thr1Meth) SNP minor T allele were more prone to RSV disease than individuals in the control group. The TLR4 (Asp299Gly), TLR4 (Thr399Ile), and JUN (c.750G/A) SNPs showed no significant association with RSV disease. It is concluded that children carrying the minor T allele of the VDR (Thr1Meth) SNP may be predisposed to RSV disease, as this SNP was identified as a risk factor for severe RSV disease in South African children, confirming the findings in the Netherlands.

Volumetric analysis of osteoclastic bioresorption of calcium phosphate ceramics with different solubilities

Commonly, to determine osteoclastic resorption of biomaterials only the resorbed area is measured. The depth of the resorption pit, however, may also be important for the performance of a material. To generate such data we used two calcium phosphate ceramics (Ca(10) and Ca(2)). The solubility of the materials was determined according to DIN EN ISO 10993-14. They were scanned three-dimensionally using infinite focus microscopy and subsequently cultivated for 4 weeks in simulated body fluid without (control) or with human osteoclasts. After this cultivation period osteoclasts number was determined and surface changes were evaluated two- and three-dimensionally. Ca(10) and Ca(2) showed solubilities of 11.0+/-0.5 and 23.0+/-2.2 mgg(-1), respectively. Both materials induced a significant increase in osteoclast number. While Ca(10) did not show osteoclastic resorption, Ca(2) showed an increased pit area and pit volume due to osteoclastic action. This was caused by an increased average pit depth and an increased number of pits, while the average area of single pits did not change significantly. The deduced volumetric osteoclastic resorption rate (vORR) of Ca(2) (0.01-0.02 microm(3)microm(-2)day(-1)) was lower than the remodelling speed observed in vivo (0.08 microm(3)microm(-2)day(-1)), which is in line with the observation that implanted resorbable materials remain in the body longer than originally expected. Determination of volumetric indices of osteoclastic resorption might be valuable in obtaining additional information about cellular resorption of bone substitute materials. This may help facilitate the development of novel materials for bone substitution.