The anti-SARS-CoV-2 monoclonal antibody, bamlanivimab, minimally impacts the endogenous immune response to COVID-19 vaccination

As the coronavirus disease 2019 (COVID-19) pandemic evolves and vaccine rollout progresses, the availability and demand for monoclonal antibodies for the prevention and treatment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are also accelerating. This longitudinal serological study evaluated the magnitude and potency of the endogenous antibody response to COVID-19 vaccination in participants who first received a COVID-19 monoclonal antibody in a prevention study. Over the course of six months, serum samples were collected from a population of nursing home residents and staff enrolled in a clinical trial who were randomized to either bamlanivimab treatment or placebo. In an unplanned component of this trial, a subset of these participants was subsequently fully vaccinated with two doses of either SpikeVax (Moderna) or Comirnaty (BioNTech/Pfizer) COVID-19 mRNA vaccines. This post-hoc analysis assessed the immune response to vaccination for 135 participants without prior SARS-CoV-2 infection. Antibody titers and potency were assessed using three assays against SARS-CoV-2 proteins that bamlanivimab does not efficiently bind to, thereby reflecting the endogenous antibody response. All bamlanivimab and placebo recipients mounted a robust immune response to full COVID-19 vaccination, irrespective of age, risk-category, and vaccine type with any observed differences of uncertain clinical importance. These findings are pertinent for informing public health policy with results that suggest that the benefit of receiving COVID-19 vaccination at the earliest opportunity outweighs the minimal effect on the endogenous immune response due to prior prophylactic COVID-19 monoclonal antibody infusion.

Efficacy and Safety of Mirikizumab in a Randomized Phase 2 Study of Patients With Crohn's Disease

BACKGROUND

Mirikizumab is a humanized monoclonal antibody targeting interleukin 23p19 with demonstrated efficacy in psoriasis and ulcerative colitis. We investigated the safety and efficacy of mirikizumab in patients with moderate-to-severe Crohn's disease (CD).

METHODS

Patients (N = 191) were randomized (2:1:1:2) to receive placebo (PBO), 200, 600, or 1000 mg mirikizumab, administered intravenously (IV) every 4 weeks. Patients who received mirikizumab and achieved ≥1 point improvement in Simple Endoscopic Score-CD at Week 12 (rerandomized maintenance cohort) were rerandomized to continue their induction IV treatment (combined IV groups [IV-C]) or receive 300 mg mirikizumab subcutaneously (SC) every 4 weeks. Nonrandomized maintenance cohort included endoscopic nonimprovers (1000 mg) and PBO patients (PBO/1000 mg) who received 1000 mg mirikizumab IV from Week 12. The primary objective was to evaluate superiority of mirikizumab to PBO in inducing endoscopic response (50% reduction from baseline in Simple Endoscopic Score-CD) at Week 12.

RESULTS

At Week 12, endoscopic response was significantly higher by the predefined 2-sided significance level of 0.1 for all mirikizumab groups compared with PBO (200 mg: 25.8%, 8/31, 95% confidence interval [CI], 10.4-41.2, P = .079; 600 mg: 37.5%, 12/32, 95% CI, 20.7-54.3, P = .003; 1000 mg: 43.8%, 28/64, 95% CI, 31.6-55.9, P < .001; PBO: 10.9 %, 7/64, 95% CI, 3.3-18.6). Endoscopic response at Week 52 was 58.5% (24/41) and 58.7% (27/46) in the IV-C and SC groups, respectively. Frequencies of adverse events (AE) in the mirikizumab groups were similar to PBO. Through Week 52, frequencies of treatment-emergent AEs were similar across all groups. Frequencies of serious AE and discontinuations due to AE were higher in the nonrandomized maintenance cohort.

CONCLUSION

Mirikizumab effectively induced endoscopic response after 12 weeks in patients with moderate-to-severe CD and demonstrated durable efficacy to Week 52. A detailed summary can be found in the Video Abstract. ClinicalTrials.gov, Number: NCT02891226.

Efficacy and Safety of Continued Treatment With Mirikizumab in a Phase 2 Trial of Patients With Ulcerative Colitis

BACKGROUND & AIMS

Mirikizumab is an antibody against the p19 subunit of interleukin 23 that has demonstrated clinical efficacy and was well tolerated following 12 weeks of induction treatment in a phase 2 trial of patients with moderate to severe ulcerative colitis. We present results of the open-label extended induction period in patients who did not initially respond to treatment with mirikizumab.

METHODS

This study was a continuation of I6T-MC-AMAC, a double-blind trial, performed at 75 sites in 14 countries, in which patients with moderate to severe ulcerative colitis were randomly assigned to 12 weeks induction therapy with 50 mg, 200 mg, or 600 mg mirikizumab or placebo. Patients without a clinical response (a 9-point decrease in Mayo subscore of ≥2 points and ≥35% from baseline and either a decrease of rectal bleeding subscore of ≥1 or a rectal bleeding subscore of 0 or 1) at week 12 were offered the opportunity to participate in an open-label, extended induction study for another 12 weeks, in which they received either 600 mg intravenous mirikizumab (n = 20) or, following a protocol amendment, 1000 mg intravenous mirikizumab (n = 64) every 4 weeks. At week 24, patients with a clinical response continued the extension maintenance period and received 200 mg subcutaneous mirikizumab. Endpoints included clinical remission (Mayo subscores of 0 for rectal bleeding, 0 or 1 with a 1-point decrease from baseline), clinical response, endoscopic remission (Mayo endoscopic subscore of 0), or endoscopic improvement (endoscopic subscore of 0 or 1), at study weeks 24 and 52. Data were analysed for patients who received mirikizumab or placebo during the induction phase of the study.

RESULTS

Among participants who did not respond to induction mirikizumab, 50.0% of those who received the 12-week extension of 600 mg mirikizumab and 43.8% who received the extension of 1000 mg mirikizumab achieved a clinical response; 15.0% and 9.4% achieved clinical remission, respectively. Endoscopic improvement was achieved by 20.0% of subjects in the 600 mg mirikizumab group and 15.6% subjects in the 1000 mg mirikizumab group. Among initial nonresponders to mirikizumab who had clinical response at study week 24 and continued into maintenance therapy, 65.8% maintained the clinical response, 26.3% achieved clinical remission, and 34.2% had endoscopic improvement at week 52. No new safety concerns were identified.

CONCLUSIONS

Extended doses of mirikizumab (600 mg and 1000 mg) for an additional 12 weeks produce a clinical response in up to 50% of patients who did not have a clinical response to 12 weeks of induction doses (50 mg, 200 mg, or 600 mg). Most of the responders to the extended doses maintained clinical response for up to 52 weeks. Clinicaltrials.gov no: NCT02589665.

Innovative clinical trial design and delivery: a phase 3 COVID-19 post-exposure prophylaxis study in skilled nursing and assisted living facilities (BLAZE-2)

The efficient community spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in the current pandemic of coronavirus disease-2019 (COVID-19), which in severe and critical cases results in progressive pulmonary infection, complicated by respiratory failure, with a high prevalence of acute respiratory distress syndrome. Of all age groups, older adults have the greatest risk of severe COVID-19 and the associated complications. Globally, there are many reports of the rapid spread of COVID-19 among residents of skilled nursing facilities, with high associated rates of morbidity and mortality. With over 1.3 million residents in nursing home care in the USA, there is an urgent need for therapeutic strategies to prevent COVID-19 in these populations.

Lilly, in collaboration with the National Institute of Allergy and Infectious Diseases, conducted the BLAZE-2 trial to evaluate the efficacy and safety of the monoclonal antibody bamlanivimab (LY3819253) in preventing SARS-CoV-2 infection and COVID-19, defined as symptomatic infection, in skilled nursing and assisted living facilities. It is a phase 3 randomized, double-blind, placebo-controlled trial, where participants were randomized to bamlanivimab (4200 mg) or placebo and then followed up for 24 weeks. Conducting a trial in the midst of a pandemic in these facilities poses several challenges, including a vulnerable elderly population, travel restrictions, supply chain interruptions, and defining the target population. The operational challenges were addressed by the innovative use of mobile research units which are customized, equipped, and staffed to support BLAZE-2 randomization and participant dosing within the skilled nursing and assisted living facilities. Herein, we describe the design of the study, the analytics behind facility selection, and an innovative operational model.

Effect of Bamlanivimab vs Placebo on Incidence of COVID-19 Among Residents and Staff of Skilled Nursing and Assisted Living Facilities: A Randomized Clinical Trial

IMPORTANCE

Preventive interventions are needed to protect residents and staff of skilled nursing and assisted living facilities from COVID-19 during outbreaks in their facilities. Bamlanivimab, a neutralizing monoclonal antibody against SARS-CoV-2, may confer rapid protection from SARS-CoV-2 infection and COVID-19.

OBJECTIVE

To determine the effect of bamlanivimab on the incidence of COVID-19 among residents and staff of skilled nursing and assisted living facilities.

DESIGN, SETTING, AND PARTICIPANTS

Randomized, double-blind, single-dose, phase 3 trial that enrolled residents and staff of 74 skilled nursing and assisted living facilities in the United States with at least 1 confirmed SARS-CoV-2 index case. A total of 1175 participants enrolled in the study from August 2 to November 20, 2020. Database lock was triggered on January 13, 2021, when all participants reached study day 57.

INTERVENTIONS

Participants were randomized to receive a single intravenous infusion of bamlanivimab, 4200 mg (n = 588), or placebo (n = 587).

MAIN OUTCOMES AND MEASURES

The primary outcome was incidence of COVID-19, defined as the detection of SARS-CoV-2 by reverse transcriptase-polymerase chain reaction and mild or worse disease severity within 21 days of detection, within 8 weeks of randomization. Key secondary outcomes included incidence of moderate or worse COVID-19 severity and incidence of SARS-CoV-2 infection.

RESULTS

The prevention population comprised a total of 966 participants (666 staff and 300 residents) who were negative at baseline for SARS-CoV-2 infection and serology (mean age, 53.0 [range, 18-104] years; 722 [74.7%] women). Bamlanivimab significantly reduced the incidence of COVID-19 in the prevention population compared with placebo (8.5% vs 15.2%; odds ratio, 0.43 [95% CI, 0.28-0.68]; P < .001; absolute risk difference, -6.6 [95% CI, -10.7 to -2.6] percentage points). Five deaths attributed to COVID-19 were reported by day 57; all occurred in the placebo group. Among 1175 participants who received study product (safety population), the rate of participants with adverse events was 20.1% in the bamlanivimab group and 18.9% in the placebo group. The most common adverse events were urinary tract infection (reported by 12 participants [2%] who received bamlanivimab and 14 [2.4%] who received placebo) and hypertension (reported by 7 participants [1.2%] who received bamlanivimab and 10 [1.7%] who received placebo).

CONCLUSIONS AND RELEVANCE

Among residents and staff in skilled nursing and assisted living facilities, treatment during August-November 2020 with bamlanivimab monotherapy reduced the incidence of COVID-19 infection. Further research is needed to assess preventive efficacy with current patterns of viral strains with combination monoclonal antibody therapy.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04497987.

Efficacy and Safety of Mirikizumab in a Randomized Phase 2 Study of Patients With Ulcerative Colitis

BACKGROUND & AIMS

Interleukin 23 contributes to the pathogenesis of ulcerative colitis (UC). We investigated the effects of mirikizumab, a monoclonal antibody against the p19 subunit of interleukin 23, in a phase 2 study of patients with UC.

METHODS

We performed a trial of the efficacy and safety of mirikizumab in patients with moderate to severely active UC, enrolling patients from 14 countries from January 2016 through September 2017. Patients were randomly assigned to groups given intravenous placebo (N = 63), mirikizumab 50 mg (N = 63) or 200 mg (N = 62) with exposure-based dosing, or mirikizumab 600 mg with fixed dosing (N = 61) at weeks 0, 4, and 8. Of assigned patients, 63% had prior exposure to a biologic agent. Clinical responders (decrease in 9-point Mayo score, including ≥2 points and ≥35% from baseline with either a decrease of rectal bleeding subscore of ≥1 or a rectal bleeding subscore of 0 or 1) at week 12 who had received mirikizumab were randomly assigned to groups that received maintenance treatment with mirikizumab 200 mg subcutaneously every 4 weeks (N = 47) or every 12 weeks (N = 46). The primary endpoint was clinical remission (Mayo subscores of 0 for rectal bleeding, with 1-point decrease from baseline for stool frequency, and 0 or 1 for endoscopy) at week 12. A multiple testing procedure was used that began with the 600-mg dose group, and any nonsignificant comparison result ended the formal statistical testing procedure.

RESULTS

At week 12, 15.9% (P = .066), 22.6% (P = .004), and 11.5% (P = .142) of patients in the 50-mg, 200-mg, and 600-mg groups achieved clinical remission, respectively, compared with 4.8% of patients given placebo. The primary endpoint was not significant (comparison to 600 mg, P > .05). Clinical responses occurred in 41.3% (P = .014), 59.7% (P < .001), and 49.2% (P = .001) of patients in the 50-mg, 200-mg, and 600-mg groups, respectively, compared with 20.6% of patients given placebo. At week 52, 46.8% of patients given subcutaneous mirikizumab 200 mg every 4 weeks and 37.0% given subcutaneous mirikizumab 200 mg every 12 weeks were in clinical remission.

CONCLUSIONS

In a randomized trial of patients with UC, mirikizumab was effective in inducing a clinical response after 12 weeks. Additional studies are required to determine the optimal dose for induction of remission. Mirikizumab showed durable efficacy throughout the maintenance period. Clinicaltrials.gov, Number NCT02589665.

A first-in-human phase 1 study of a hepcidin monoclonal antibody, LY2787106, in cancer-associated anemia

Background

Hepcidin plays a central role in iron homeostasis and erythropoiesis. Neutralizing hepcidin with a monoclonal antibody (mAb) may prevent ferroportin internalization, restore iron efflux from cells, and allow transferrin-mediated iron transport to the bone marrow. This multicenter, phase 1 study evaluated the safety, pharmacokinetics (PK), pharmacodynamics (PD), and efficacy of a fully humanized mAb (LY2787106) with high affinity for hepcidin in cancer patients with anemia.

Methods

Thirty-three patients with hepcidin levels ≥5 ng/mL received LY2787106 either every 3 weeks (19 patients, dose range 0.3–10 mg/kg) (part A) or weekly (14 patients, dose 10 mg/kg) (part B). LY2787106 PK/PD markers of iron and hematology biology were measured.

Results

LY2787106 clearance (32 mL/h) and volume of distribution (7.7 L) were independent of dose and time, leading to a dose-proportional increase in concentration with dose. Consistent dose-dependent increases in serum iron, and transferrin saturation were seen at the 3 and 10 mg/kg dose levels, typically peaking within 24 h after LY2787106 administration and returning to baseline by day 8.

Conclusions

Our findings indicate that LY2787106 was well tolerated in cancer patients with anemia and that targeting the hepcidin-ferroportin pathway by neutralizing hepcidin resulted in transient iron mobilization, thus supporting the role of hepcidin in iron regulation.

Trial registration

ClinicalTrial.gov, NCT01340976

Electronic supplementary material

The online version of this article (doi:10.1186/s13045-017-0427-x) contains supplementary material, which is available to authorized users.

Impaired collateral artery development in spontaneously hypertensive rats

OBJECTIVE

To determine whether collateral artery development is impaired in spontaneously hypertensive (SHR) relative to normotensive (WKY) rats.

METHODS

Sequential mesenteric arteries were ligated to create a collateral pathway responsible for the perfusion of approximately 50 first-order arterioles. Collateral development was assessed by measurement of in vivo arterial diameter before and 1 week after ligation. Histological and morphometric measurements were made from cross-sectional preparations of these arteries to evaluate intimal and medial cell numbers and medial area. eNOS expression was evaluated with Western blotting.

RESULTS

One week after arterial ligation, collateral diameter was increased more in WKY than SHR both absolutely (137 +/- 9.1 versus 99 +/- 8.6 microm) and relative to same-animal controls (38 +/- 5.5% versus 13 +/- 7.1%). At the time of model creation, blood flow was elevated to comparable levels in both WKY and SHR, and wall shear rate in the SHR collateral was greater than both the SHR control and WKY collateral arteries. Endothelial cell number in arterial cross-section was increased in collaterals by 80% in WKY and only 22% in the SHR. eNOS expression was increased in the WKY (128%) but not in the SHR collateral.

CONCLUSIONS

For equivalent arterial occlusion, the data demonstrate that collateral development is suppressed in the SHR as indicated by luminal expansion. This impairment of luminal expansion is associated with a decreased endothelial proliferation and the lack of an increase in eNOS expression.

Impaired collateral development in mature rats

The effect of maturation on collateral development of resistance arteries was investigated. Three to four sequential mesenteric arteries were ligated to create collateral pathways in anesthetized young (approximately 200 g) and mature (approximately 600 g) rats. Blood flow was similarly elevated in collaterals of young and mature animals. In vivo inner arterial diameter was increased only within young collaterals (33 +/- 7%, P < 0.001). Increases in number of intimal nuclei (57 +/- 10% vs. 52 +/- 14%) and cross-sectional medial area (33 +/- 13% vs. 38 +/- 5%) were similar between young and mature collaterals. Relative to the same animal controls, collateral endothelial nitric oxide synthase mRNA was increased as much in mature as in young rats. Proteomic analysis revealed significant differences in protein expression with maturation between control arteries as well as flow-loaded collateral vessels. The results indicate that, whereas intimal and medial remodeling events were similar in collaterals of young and mature rats, luminal expansion occurred only in young rats. Alteration in arterial protein expression with maturation and altered responses to stimuli for collateral development may contribute to this impairment.

Shear level influences resistance artery remodeling: wall dimensions, cell density, and eNOS expression

The magnitude of shear stimulus has been shown to determine the level of growth factor expression in cell culture. However, little is known regarding what effect shear level has on specific arterial wall remodeling events in vivo. We have hypothesized that the rate of luminal diameter change and specific remodeling events within the arterial wall layers are dependent on shear level. Selective ligations were made to alter the number of microvascular perfusion units of mesenteric arteries within the same animal to approximately 50%, 200%, and 400% of control. Arterial blood flow and wall shear rate were correlated with the degree of alteration in perfusion units. Luminal diameters were decreased in 50% arteries by day 2 and increased approximately 17% and 33% respectively, in 200% and 400% arteries at day 7. The rate of diameter change was greatest in 50% and 400% arteries. Wall areas (medial +37%; intimal +18% at day 2) and cell densities (intimal +26%; adventitial +44% at day 2) were altered only in the 400% arteries. A positive correlation existed by day 2 between endothelial staining for endothelial nitric oxide synthase and shear level. The results demonstrate that shear level influences the rate of luminal expansion, specific remodeling events within each wall layer, and the degree of endothelial gene expression. A greater understanding of how shear level influences specific remodeling events within each wall layer should aid in the development of targeted therapies to manipulate the remodeling process in health and disease.

Nitric oxide release during alpha1-adrenoceptor-mediated constriction of arterioles

We examined endothelial modulation of norepinephrine (NE)-mediated constriction in isolated, cannulated, first-order arterioles from skeletal muscle of rats. Acute arteriolar constrictor responses to NE (10(-9) to 10(-7) M) were significantly (P < 0.05) enhanced after either endothelial denudation or inhibition of nitric oxide synthase with NG-monomethyl-L-arginine (10(-4) M, 30 min). In contrast, arteriolar constrictions to NE were not different after treatment with either the cyclooxygenase inhibitor diclofenac (10(-6) M, 30 min) or the K+-channel blocker tetrabutylammonium (5 x 10(-5) M, 30 min). We also measured arteriolar responses to the vasoconstrictor PGF2alpha; responses were not altered by any of the experimental treatments, which indicates that this phenomenon is not ubiquitous to all vasoconstricting agents. Mechanistically, we examined vascular smooth muscle (VSM) and endothelial cell calcium. Both NE and PGF2alpha significantly increased VSM cell calcium measurements; however, endothelial cell calcium was significantly increased with NE or phenylephrine (an alpha1-adrenergic agonist) but not with PGF2alpha or UK-14304 (an alpha2-adrenergic agonist). Together these findings suggest that in rat cremaster first-order arterioles, NE stimulates an increase in VSM calcium via adrenergic receptors with subsequent increase in endothelial cell calcium, possibly via stimulation of alpha1-adrenergic receptors on the arteriolar endothelium. The burst in endothelial cell calcium may then lead to the production of nitric oxide, which diffuses to the VSM, attenuates constriction, and maintains at least some minimal level of blood flow.

Fast and reliable extraction of protozoan parasite DNA from fecal specimens

BACKGROUND

Polymerase chain reaction (PCR) detection of intestinal protozoa in fecal specimens is hampered by poor recovery of DNA and by the presence of PCR inhibitors. In this study we describe a novel method for DNA extraction from such specimens containing spores and oocysts of Enterocytozoon bieneusi and Cryptosporidium parvum, respectively.

METHODS AND RESULTS

Extraction was done using commercial kits modified to maximize the recovery and purity of extracted DNA. In comparison with a procedure we previously reported, we estimate that this method may increase the sensitivity of parasite DNA detection in fecal specimens up to tenfold. An additional advantage of this method is that up to 12 samples may be processed simultaneously within 2 hours.

CONCLUSIONS

By using this method, we were able to increase reproducibility of PCR amplification on fecal specimens and significantly reduce the hands-on time required to process the samples.

Effect of acute potassium-magnesium aspartate supplementation on ammonia concentrations during and after resistance training

This study examined the effects of aspartate supplementation (ASP) on plasma ammonia concentrations ([NH4+]) during and after a resistance training workout (RTW). Twelve male weight trainers were randomly administered ASP or vitamin C in a crossover, double blind protocol, each trial separated by 1 wk. ASP and vitamin C were given over a 2-hr period beginning 5 hr prior to the RTW. The RTW consisted of bench, incline, shoulder, and triceps presses, and biceps curls at 70% of one repetition maximum (1-RM). After the RTW a bench press test (BPT) to failure at 65% of 1-RM was used to assess performance. [NH4+] was determined preexercise, 20 and 40 min midworkout, immediately postexercise, and 15 min postexercise. Treatment-by-time ANOVAs, paired t tests, and contrast comparisons were used to identify mean differences. No significant differences were observed between treatments for [NH4+] or BPT. [NH4+] increased significantly from Pre to immediately postexercise for both the ASP and vitamin C trials. Acute ASP supplementation does not reduce [NH4+] during and after a high intensity RTW in weight trained subjects.

Metabolic and hemodynamic responses to walking with hand weights in older individuals

The purpose of this study was to examine metabolic and hemodynamic responses of older adults (age = 66.2 +/- 5.6 yr) to walking with hand-held weights (HHW). Nineteen volunteers participated in eight randomly assigned, 10-min, submaximal, self-selected constant speed (CSP) or constant heart rate (CHR) exercise bouts using the following HHW conditions: no weight, W0; 0.45 kg, W1; 1.36 kg, W3; 2.27 kg, W5. Oxygen uptake (VO2) was recorded every 30 s, heart rate (HR) each minute, and blood pressure (BP) every 2 min. Mean values for the last 5 min of exercise were analyzed using repeated measures ANOVA. Contrast comparison tests were used to determine differences among means. During CS, significant differences between means (P < or = 0.05) existed for: VO2 (W0, W1 < W3, W5); HR, SBP, DBP, SBPmax, DBPmax (W0 < W1, W3, W5); HR, rate pressure product (RPP), DBPmax (W1 < W5); SBP, DBP, SBPmax, RPP (W3 < W5). During CHR, significant differences (P < or = 0.05) between means existed for: SBP, DBP, RPP (W0, W1, W3 < W5); DBP (W0 < W3; W1, W3 < W5). These results indicate that the use of HHW significantly increases metabolic responses at W3 and W5 during CS exercise in older adults, while hemodynamic responses increase significantly across HHW for both CS and CHR. Due to the increases in hemodynamic responses, the use of HHW may be contraindicated for older individuals with suspected or diagnosed cardiovascular disease.