SARS-CoV-2 recombinant spike ferritin nanoparticle vaccine adjuvanted with Army Liposome Formulation containing monophosphoryl lipid A and QS-21: a phase 1, randomised, double-blind, placebo-controlled, first-in-human clinical trial

BACKGROUND

A self-assembling SARS-CoV-2 WA-1 recombinant spike ferritin nanoparticle (SpFN) vaccine co-formulated with Army Liposomal Formulation (ALFQ) adjuvant containing monophosphoryl lipid A and QS-21 (SpFN/ALFQ) has shown protective efficacy in animal challenge models. This trial aims to assess the safety and immunogenicity of SpFN/ALFQ in a first-in-human clinical trial.

METHODS

In this phase 1, randomised, double-blind, placebo-controlled, first-in-human clinical trial, adults were randomly assigned (5:5:2) to receive 25 μg or 50 μg of SpFN/ALFQ or saline placebo intramuscularly at day 1 and day 29, with an optional open-label third vaccination at day 181. Enrolment and randomisation occurred sequentially by group; randomisation was done by an interactive web-based randomisation system and only designated unmasked study personnel had access to the randomisation code. Adults were required to be seronegative and unvaccinated for inclusion. Local and systemic reactogenicity, adverse events, binding and neutralising antibodies, and antigen-specific T-cell responses were quantified. For safety analyses, exact 95% Clopper-Pearson CIs for the probability of any incidence of an unsolicited adverse event was computed for each group. For immunogenicity results, CIs for binary variables were computed using the exact Clopper-Pearson methodology, while CIs for geometric mean titres were based on 10 000 empirical bootstrap samples. Post-hoc, paired one-sample t tests were used to assess the increase in mean log-10 neutralising antibody titres between day 29 and day 43 (after the second vaccination) for the primary SARS-CoV-2 targets of interest. This trial is registered at ClinicalTrials.gov, NCT04784767, and is closed to new participants.

FINDINGS

Between April 7, and June 29, 2021, 29 participants were enrolled in the study. 20 individuals were assigned to receive 25 μg SpFN/ALFQ, four to 50 μg SpFN/ALFQ, and five to placebo. Neutralising antibody responses peaked at day 43, 2 weeks after the second dose. Neutralisation activity against multiple omicron subvariants decayed more slowly than against the D614G or beta variants until 5 months after second vaccination for both dose groups. CD4+ T-cell responses were elicited 4 weeks after the first dose and were boosted after a second dose of SpFN/ALFQ for both dose groups. Neutralising antibody titres against early omicron subvariants and clade 1 sarbecoviruses were detectable after two immunisations and peaked after the third immunisation for both dose groups. Neutralising antibody titres against XBB.1.5 were detected after three vaccinations. Passive IgG transfer from vaccinated volunteers into Syrian golden hamsters controlled replication of SARS-CoV-1 after challenge.

INTERPRETATION

SpFN/ALFQ was well tolerated and elicited robust and durable binding antibody and neutralising antibody titres against a broad panel of SARS-CoV-2 variants and other sarbecoviruses.

FUNDING

US Department of Defense, Defense Health Agency.

Florida-California Cancer Health Equity Center (CaRE2) Community Scientist Research Advocacy Program

The Community Scientist Program (CSP), a model connecting researchers with community members, is effective to inform and involve the general population in health-related clinical research. Given the existing cancer disparities among Black/African American and Hispanic/Latino/a populations, more models describing how cancer-related CSPs are designed, implemented, and evaluated are needed. The Florida-California Cancer Research, Education and Engagement (CaRE2) Health Equity Center is a tri-institutional, bicoastal center created to eliminate cancer health disparities among Black/African American and Hispanic/Latino/a populations living in California and in Florida. The CaRE2 Center created a Community Scientist Research Advocacy (CSRA) training program for community members to become cancer research advocates. The CSRA program is currently a 13-week program conducted 100% virtually with all materials provided in English and Spanish for participants to learn more about prostate, lung, and pancreas cancers, ongoing research at CaRE2, and ways to share cancer research throughout their communities. Participants attend didactic lectures on cancer research during weeks 1-5. In week 4, participants join CSRA self-selected groups based on cancer-related topics of interest. Each group presents their cancer-related advocacy project developed during weeks 5-12 at the final session. In this paper, we describe the CaRE2 Health Equity Center's CSRA program, share results, and discuss opportunities for improvement in future program evaluation as well as replication of this model in other communities.

Socioeconomic, health-care access and clinical determinants of disease severity in Multiple Sclerosis in Chile

BACKGROUND

MS severity may be affected by genetic, patient-related, disease-related and environmental factors. Socioeconomic status, including income and healthcare access, amongst others, may also have a role in affecting diagnostic delay or therapy prescription. In Chile, two main healthcare systems exist, public-healthcare and private-healthcare, nonetheless universal care laws (e.g., access to High Efficacy Therapy-HET), including both systems, have been recently enacted for people with MS.

OBJECTIVE

To assess the role of Socioeconomic Conditions (SEC), clinical variables and public health policies on the impact of disease severity of MS patients in Chile.

METHODS

Multicentric, observational, cross-sectional study including patients from two reference centres (1 national reference centre from the private-health system and 1 regional reference centre from the public-health system). SEC and clinical variables included healthcare insurance (private or public), subclassification of health insurance according to monthly income, sex, age at onset, diagnostic delay, disease duration, diagnosis before HET law (as a proxy of HET delay), and current HET treatment. Progression Index (PI), EDSS ≥6.0 and Progressive MS diagnosis were used as outcome measures. Multivariable binary logistic regression was performed.

RESULTS

We included 604 patients (460 private-health, 144 public-health), 67% women, 100% white/mestizo, 88% RRMS, mean age 42±12 years, mean age at onset 32±11 years, mean disease duration 10±6 years, median diagnostic delay 0 (0-34) years, 86% currently receiving any DMT, 55% currently receiving HET, median EDSS at last visit of 2.0 (0-10), and median PI 0.17 (0-4.5). Lower monthly income was associated with higher EDSS and higher PI. In the multivariable analysis, public-healthcare (OR 10.2), being diagnosed before HET-law (OR 4.89), longer diagnostic delay (OR 1.26), and older age at onset (OR 1.05) were associated with a higher risk of PI>0.2, while current HET (OR 0.39) was a protective factor. Diagnosis before HET-law (OR 7.59), public-healthcare (OR 6.49), male sex (OR 2.56), longer disease duration (OR 1.2) and older age at onset (OR 1.1) were associated with a higher risk of Progressive MS. Public-healthcare (OR 5.54), longer disease duration (OR 1.14) and older age at onset (OR 1.08) were associated with a higher risk of EDSS ≥6.0 while current treatment with HET had a trend as being a protective factor (OR 0.44, p = 0.05).

CONCLUSION

MS severity is impacted by non-modifiable factors such as sex and age at onset. Interventions focused on shortening diagnostic delay and encouraging early access to high-efficacy therapies, as well as initiatives that may reduce the disparities inherent to lower socioeconomic status, may improve outcomes in people with MS.

Multidose Priming and Delayed Boosting Improve Plasmodium falciparum Sporozoite Vaccine Efficacy Against Heterologous P. falciparum Controlled Human Malaria Infection

Background

A live-attenuated Plasmodium falciparum sporozoite (SPZ) vaccine (PfSPZ Vaccine) has shown up to 100% protection against controlled human malaria infection (CHMI) using homologous parasites (same P. falciparum strain as in the vaccine). Using a more stringent CHMI, with heterologous parasites (different P. falciparum strain), we assessed the impact of higher PfSPZ doses, a novel multi-dose prime regimen, and a delayed vaccine boost upon vaccine efficacy (VE).

Methods

We immunized 4 groups that each contained 15 healthy, malaria-naive adults. Group 1 received 5 doses of 4.5 x 105 PfSPZ (Days 1, 3, 5, and 7; Week 16). Groups 2, 3, and 4 received 3 doses (Weeks 0, 8, and 16), with Group 2 receiving 9.0 × 105/doses; Group 3 receiving 18.0 × 105/doses; and Group 4 receiving 27.0 × 105 for dose 1 and 9.0 × 105 for doses 2 and 3. VE was assessed by heterologous CHMI after 12 or 24 weeks. Volunteers not protected at 12 weeks were boosted prior to repeat CHMI at 24 weeks.

Results

At 12-week CHMI, 6/15 (40%) participants in Group 1 (P = .04) and 3/15 (20%) participants in Group 2 remained aparasitemic, as compared to 0/8 controls. At 24-week CHMI, 3/13 (23%) participants in Group 3 and 3/14 (21%) participants in Group 4 remained aparasitemic, versus 0/8 controls (Groups 2–4, VE not significant). Postboost, 9/14 (64%) participants versus 0/8 controls remained aparasitemic (3/6 in Group 1, P = .025; 6/8 in Group 2, P = .002).

Conclusions

Administering 4 stacked priming injections (multi-dose priming) resulted in 40% VE against heterologous CHMI, while dose escalation of PfSPZ using single-dose priming was not significantly protective. Boosting unprotected subjects improved VE at 24 weeks, to 64%.

Clinical Trials Registration

NCT02601716.

IMRAS-A clinical trial of mosquito-bite immunization with live, radiation-attenuated P. falciparum sporozoites: Impact of immunization parameters on protective efficacy and generation of a repository of immunologic reagents

Background

Immunization with radiation-attenuated sporozoites (RAS) by mosquito bite provides >90% sterile protection against Plasmodium falciparum (Pf) malaria in humans. RAS invade hepatocytes but do not replicate. CD8+ T cells recognizing parasite-derived peptides on the surface of infected hepatocytes are likely the primary protective mechanism. We conducted a randomized clinical trial of RAS immunization to assess safety, to achieve 50% vaccine efficacy (VE) against controlled human malaria infection (CHMI), and to generate reagents from protected and non-protected subjects for future identification of protective immune mechanisms and antigens.

Methods

Two cohorts (Cohort 1 and Cohort 2) of healthy, malaria-naïve, non-pregnant adults age 18–50 received five monthly immunizations with infected (true-immunized, n = 21) or non-infected (mock-immunized, n = 5) mosquito bites and underwent homologous CHMI at 3 weeks. Immunization parameters were selected for 50% protection based on prior clinical data. Leukapheresis was done to collect plasma and peripheral blood mononuclear cells.

Results

Adverse event rates were similar in true- and mock-immunized subjects. Two true- and two mock-immunized subjects developed large local reactions likely caused by mosquito salivary gland antigens. In Cohort 1, 11 subjects received 810–1235 infected bites; 6/11 (55%) were protected against CHMI vs. 0/3 mock-immunized and 0/6 infectivity controls (VE 55%). In Cohort 2, 10 subjects received 839–1131 infected bites with a higher first dose and a reduced fifth dose; 9/10 (90%) were protected vs. 0/2 mock-immunized and 0/6 controls (VE 90%). Three/3 (100%) protected subjects administered three booster immunizations were protected against repeat CHMI vs. 0/6 controls (VE 100%). Cohort 2 uniquely showed a significant rise in IFN-γ responses after the third and fifth immunizations and higher antibody responses to CSP.

Conclusions

PfRAS were generally safe and well tolerated. Cohort 2 had a higher first dose, reduced final dose, higher antibody responses to CSP and significant rise of IFN-γ responses after the third and fifth immunizations. Whether any of these factors contributed to increased protection in Cohort 2 requires further investigation. A cryobank of sera and cells from protected and non-protected individuals was generated for future immunological studies and antigen discovery.

Trial registration

ClinicalTrials.gov NCT01994525.

Age-related decline in female fertility is not due to diminished capacity of the uterus to sustain embryo implantation

OBJECTIVE

To evaluate the contribution of the uterus to age-related reproductive failure in women.

PATIENTS

Thirty-eight ovum donors (30.2 +/- 4.9 years [mean +/- SD]) donating oocytes throughout 102 ovum donations. Fifty-one cycles were documented in "younger" recipients (35.8 +/- 3.1 years) and 51 in "older" recipients (44.0 +/- 3.1 years). The study was prospectively designed; same-cohort oocytes obtained from one young donor during a specific cycle were evenly distributed between "young" and "old" ovum recipients. Use of oocytes from a single source and a unique ovulatory cohort provides strict control over oocyte quality. Uterine age is varied by design, according to the age of the recipient at the time of ET. The role of the aging uterus in the decline of female fertility can be thus isolated and scrutinized.

RESULTS

No significant (NS) difference in the number of ova received (7.9 +/- 3.4 versus 7.0 +/- 3.5), ova fertilized (4.4 +/- 1.5 versus 4.5 +/- 2.3), or embryos transferred (4.1 +/- 1.5 versus 4.1 +/- 1.6) was observed between the < 40 and > or = 40 recipient age groups. A total of 23 pregnancies occurred among the 102 ETs (22.6%). Eleven clinical pregnancies (21.6%) resulting in 10 deliveries were observed in the < 40 recipient age group, and 12 clinical pregnancies (23.5%) leading to 10 deliveries occurred in the > or = 40 recipient age group (NS). The pregnancy loss rates were 9.1% (1 of 11) and 16.7% (2 of 12) for the two recipient age groups, respectively, (NS).

CONCLUSION

The capacity to conceive and to gestate a conception to term when oocyte quality is controlled appears to be independent of uterine aging through the fifth decade of life.

Premature luteinization in controlled ovarian hyperstimulation has no adverse effect on oocyte and embryo quality

OBJECTIVE

To determine if premature luteinization has an adverse effect on oocyte and, hence, embryo quality.

DESIGN

Retrospective evaluation of anonymous ovum donors/oocyte recipients.

SETTING

A large oocyte donation program.

PATIENTS, PARTICIPANTS

Sixty-eight women undergoing controlled ovarian hyperstimulation (COH) as ovum donors were matched to 68 women with ovarian failure as ovum recipients who had endometrial maturation exogenously controlled by an identical hormone replacement protocol.

INTERVENTIONS

Serum was collected for E2 and P in donors and recipients.

MAIN OUTCOME MEASURES

The incidence of premature luteinization was determined in donors. Cycle characteristics were compared between donors with and without premature luteinization, with emphasis on oocyte and embryo quality. Implantation rates per embryo and delivery rates per transfer were measured in recipients.

RESULTS

Twenty-one (31%) of the donors demonstrated premature luteinization. Serum P was higher on day before hCG, day of hCG, and day after hCG in women demonstrating premature luteinization. However, there were no differences between donor cycles with or without premature luteinization as determined by donor age, ampules of gonadotropins used, day of hCG administration, peak E2, total number of oocytes, and number of mature oocytes retrieved. Ovum recipients were of similar age and had similar E2 exposure (area under the E2 curve) before P administration. Similar fertilization rates, incidence of polyspermia, number of embryos transferred of similar embryo grade, and similar implantation rates and deliveries per transfer were observed in women receiving oocytes from donors with and without premature luteinization, respectively.

CONCLUSIONS

Similar oocyte quality, fertilization, and polyspermia rates, embryo quality, implantation, and delivery rates suggest that any negative impact of premature luteinization on pregnancy rates in COH cycles from young women is not due to an adverse effect of PL on oocyte and hence embryo quality, but rather on the endometrial environment.

Premature luteinization is not eliminated by pituitary desensitization with leuprolide acetate in women undergoing gonadotrophin stimulation who demonstrated premature luteinization in a prior gonadotrophin-only cycle

A total of 40 women who demonstrated premature luteinization (serum progesterone > or = 3.5 nmol/l (1.1 ng/ml) on or before the day of human chorionic gonadotrophin (HCG) administration) during ovarian stimulation with human menopausal gonadotrophins (HMG) were restimulated in 46 subsequent cycles after pituitary desensitization with the gonadotrophin-releasing hormone agonist (GnRHa, 1 mg), leuprolide acetate. Five women were treated with a double dose of agonist (2 mg) when premature luteinization was determined on the single dose protocol. In HMG-only cycles, a frank luteinizing hormone (LH) surge was detected in 30 cycles; 15 cycles were cancelled because of premature ovulation. In agonist cycles there were no cancellations, although 25 cycles demonstrated premature luteinization and in six cycles a frank LH surge was detected. Doubling the dose of the agonist did not prevent premature luteinization. Agonist cycles with and without premature luteinization did not differ in any in-vitro fertilization (IVF) outcome parameters (ampoules of gonadotrophins, day of HCG administration, peak oestradiol concentration, number of oocytes retrieved, fertilized, transferred or cryopreserved). We conclude that in patients who demonstrate premature luteinization in a gonadotrophin-only cycle, pituitary desensitization may not completely eliminate subtle luteinization or a frank LH surge.

The effect of female antisperm antibodies on in vitro fertilization, early embryonic development, and pregnancy outcome

STUDY OBJECTIVE

To evaluate the extent to which human in vitro fertilization-embryo transfer (IVF-ET) alleviates immunological infertility.

DESIGN

Retrospective.

SETTING

In vitro fertilization program.

PATIENTS

Thirty-three patients with positive antisperm antibodies undergoing 50 cycles of IVF-ET in which maternal serum was replaced by 5 mg/mL of bovine serum albumin (BSA) comprised the study group. Seventy-one patients with tubal infertility served as controls. In 50 of these, medium was supplemented with 7.5% maternal serum, and 21 were assigned to BSA substitution.

RESULTS

Percentage of fertilization in the study group was significantly lower (41 +/- 31; mean +/- SD) than that of controls with maternal serum (77 +/- 15) and BSA (76 +/- 22). Early embryonic quality, as assessed by percentage of cleavage and morphological grading, was found to be inferior in patients with antisperm antibodies. The percentage of advanced embryos (greater than or equal to 4 blastomeres) at the time of transfer was 42 +/- 39 in the study group, compared with 65 +/- 23 and 75 +/- 35 for maternal serum and BSA controls, respectively. Percentage of morphologically favorable embryos (grades 1 and 2 in a 1 to 5 grading system) was 49 +/- 31 in the study group, compared with 78 +/- 35 and 74 +/- 23 for the controls. Percentage of clinical pregnancy was somewhat lower in the study group (12.5%) than in controls with either maternal serum (18%) or BSA (19%).

CONCLUSIONS

Antisperm antibodies may have an adverse effect on fertilization and early embryonic development. Female immunological infertility may not be completely alleviated by IVF-ET.

Poor oocyte quality rather than implantation failure as a cause of age-related decline in female fertility

Female fertility declines with advancing age. To establish whether this age-related reproductive failure results from diminished oocyte quality or uterine/endometrial inadequacy we investigated ovum donation in 35 infertile women, aged 40 years or older (mean 42.7 [SE 0.3]) who had failed at attempts at conception with their own (self) oocytes. Oocytes were donated by 29 young individuals (mean age 33.4 [0.7]) undergoing in-vitro fertilisation (IVF). 8 (5.3%) pregnancies were achieved in 150 cycles of ovulation induction with self-oocytes and 2 (3.3%) in 60 such cycles by in-vitro fertilisation (IVF), but none attained viability. By contrast in 50 cycles with donated oocytes 28 (56%) pregnancies and 15 (30%) deliveries were realised (p less than 0.005). The rate of implantation per embryo transferred was higher (14.7%) with donated oocytes than that with self-oocytes (3.3%) (p less than 0.01). To further elucidate the contribution of age to reproductive outcome, pregnancy results were compared between the young donors and older recipients. Both donors and recipients shared oocytes from the same induced cohort. Rates for clinical pregnancy and delivery did not differ between donors (33% and 23%) and recipients (40% and 30%). Our data suggest that the age-related decline in female fertility is attributable to oocyte quality and is correctable by ovum donation. The uterus can adequately sustain pregnancies even when reproductive potential is artificially prolonged into the late 40s.

An insight into early reproductive processes through the in vivo model of ovum donation

To gain insight into early reproductive processes we have prospectively designed ovum donation protocols to elucidate several phenomena relating to embryo implantation and pregnancy sustenance. Artificial endometrial cycles with variable follicular phases were induced in 60 recipients by sequential estrogen and progesterone. A total of 964 oocytes were retrieved throughout 43 ovum donation attempts, for an average of 22.4 (range, 16-41) eggs/retrieval. The overall delivery rate per egg retrieval (donors and recipients combined) was 72.1% (31 of 43). The shortest estrogen stimulation (short follicular phase) resulting in ongoing pregnancies was 5 days in duration, while the longest (long follicular phase) was 35 days in duration before progesterone initiation. Utilization of variable length follicular phases, artificially extended the stage of endometrial receptivity to over 4 weeks. To assess the window of implantation, same age embryos were transferred onto endometrium of different maturational stages. Pregnancies were documented with embryo transfers between luteal day 1 (day 15) to luteal day 6 (day 20), extending the window of implantation in the human to at least 6 consecutive days. To evaluate the relative contribution of oocyte quality and endometrial receptivity to pregnancy outcome, common source ova were transferred onto endometrium with variable hormonal exposure. Despite the drastically different follicular phase estradiol levels and periods of exposure, similar delivery rates were attained in donor cycles (29.4%) and recipient cycles during short follicular phases (29.6%). Slightly higher delivery rates (39.4%) were observed with long follicular phases. The comparable pregnancy rates in donors and recipients are attributed to the common source oocytes regardless of endometrial stimulation.