Two Phase 1, Randomized, Double-Blind, Placebo-Controlled, Single-Ascending-Dose Studies To Investigate the Safety, Tolerability, and Pharmacokinetics of an Anti-Influenza A Virus Monoclonal Antibody, MHAA4549A, in Healthy Volunteers.

Hospitalized patients with severe influenza are at significant risk for morbidity and mortality. MHAA4549A is a human monoclonal immunoglobulin (Ig) G1 antibody that binds to a highly conserved stalk region of the influenza A virus hemagglutinin protein and neutralizes all tested seasonal human influenza A virus strains. Two phase 1 trials examined the safety, tolerability, and pharmacokinetics of MHAA4549A in healthy volunteers. Both single ascending-dose trials were randomized, double blinded, and placebo controlled. Trial 1 randomized 21 healthy adults into four cohorts receiving a single intravenous dose of 1.5, 5, 15, or 45 mg/kg MHAA4549A or placebo. Trial 2 randomized 14 healthy adults into two cohorts receiving a single intravenous fixed dose of 8,400 mg or 10,800 mg of MHAA4549A or placebo. Subjects were followed for 120 days after dosing. No subject was discontinued in either trial, and no serious adverse events were reported. The most common adverse event in both studies was mild headache (trial 1, 4/16 subjects receiving MHAA4549A and 1/5 receiving placebo; trial 2, 4/8 subjects receiving MHAA4549A and 2/6 receiving placebo). MHAA4549A produced no relevant time- or dose-related changes in laboratory values or vital signs compared to those with placebo. No subjects developed an antitherapeutic antibody response following MHAA4549A administration. MHAA4549A showed linear serum pharmacokinetics, with a mean half-life of 22.5 to 23.7 days. MHAA4549A is safe and well tolerated in healthy volunteers up to a single intravenous dose of 10,800 mg and demonstrates linear serum pharmacokinetics consistent with those of a human IgG1 antibody lacking known endogenous targets in humans. (These trials have been registered at ClinicalTrials.gov under registration no. NCT01877785 and NCT02284607).

Lim JJ ，Deng R ，Derby MA ，Larouche R ，Horn P ，Anderson M ，Maia M ，Carrier S ，Pelletier I ，Burgess T ，Kulkarni P ，Newton E ，Tavel JA ... -  《-》

Phase 2 Randomized Trial of the Safety and Efficacy of MHAA4549A, a Broadly Neutralizing Monoclonal Antibody, in a Human Influenza A Virus Challenge Model.

MHAA4549A, a human monoclonal antibody targeting the hemagglutinin stalk region of influenza A virus (IAV), is being developed as a therapeutic for patients hospitalized with severe IAV infection. The safety and efficacy of MHAA4549A were assessed in a randomized, double-blind, placebo-controlled, dose-ranging study in a human IAV challenge model. One hundred healthy volunteers were inoculated with A/Wisconsin/67/2005 (H3N2) IAV and, 24 to 36 h later, administered a single intravenous dose of either placebo, MHAA4549A (400, 1,200, or 3,600 mg), or a standard oral dose of oseltamivir. Subjects were assessed for safety, pharmacokinetics (PK), and immunogenicity. The intent-to-treat-infected (ITTI) population was assessed for changes in viral load, influenza symptoms, and inflammatory biomarkers. MHAA4549A was well tolerated in all IAV challenge subjects. The 3,600-mg dose of MHAA4549A significantly reduced the viral burden relative to that of the placebo as determined by the area under the curve (AUC) of nasopharyngeal virus infection, quantified using quantitative PCR (98%) and 50% tissue culture infective dose (TCID50) (100%) assays. Peak viral load, duration of viral shedding, influenza symptom scores, mucus weight, and inflammatory biomarkers were also reduced. Serum PK was linear with a half-life of ∼23 days. No MHAA4549A-treated subjects developed anti-drug antibodies. In conclusion, MHAA4549A was well tolerated and demonstrated statistically significant and substantial antiviral activity in an IAV challenge model. (This study has been registered at ClinicalTrials.gov under identifier NCT01980966.).

McBride JM ，Lim JJ ，Burgess T ，Deng R ，Derby MA ，Maia M ，Horn P ，Siddiqui O ，Sheinson D ，Chen-Harris H ，Newton EM ，Fillos D ，Nazzal D ，Rosenberger CM ，Ohlson MB ，Lambkin-Williams R ，Fathi H ，Harris JM ，Tavel JA ... -  《-》

Pharmacokinetics of MHAA4549A, an Anti-Influenza A Monoclonal Antibody, in Healthy Subjects Challenged with Influenza A Virus in a Phase IIa Randomized Trial.

Deng R ，Lee AP ，Maia M ，Lim JJ ，Burgess T ，Horn P ，Derby MA ，Newton E ，Tavel JA ，Hanley WD ... -  《-》

A Phase 1, Randomized, Double-Blind, Placebo-Controlled, Single-Ascending-Dose Study To Investigate the Safety, Tolerability, and Pharmacokinetics of an Anti-Influenza B Virus Monoclonal Antibody, MHAB5553A, in Healthy Volunteers.

Influenza B can cause significant morbidity and mortality. MHAB5553A, a human monoclonal immunoglobulin G1 (IgG1) antibody that binds to a highly conserved region of the hemagglutinin protein of influenza B virus, is being examined as a novel therapeutic for the treatment of influenza B patients with severe disease. This phase 1, randomized, double-blind, placebo-controlled, single-ascending-dose study was conducted to assess the safety, tolerability, and pharmacokinetics (PK) of MHAB5553A. Twenty-six healthy male and female volunteers of >18 years of age were randomized into five cohorts receiving a single intravenous (i.v.) dose of 120, 1,200, 3,600, 8,400, or 10,800 mg MHAB5553A or placebo (four active:one placebo, except for the 120-mg cohort [4:2]). Subjects were followed for 120 days after dosing. No subject discontinued the study, no dose-limiting adverse events or serious adverse events were reported, and a maximum tolerated dose (MTD) was not defined. The most commonly reported adverse events were cold symptoms and headache; most were mild and occurred at a similar rate across all cohorts. MHAB5553A showed no relevant time- or dose-related changes in laboratory values or vital signs compared to the placebo. The observed serum PK was linear and generally dose proportional, and the observed nasal PK was nonlinear and generally non-dose proportional. MHAB5553A is generally well tolerated in healthy volunteers up to at least a single i.v. dose of 10,800 mg and demonstrated linear serum PK consistent with those of a human IgG1 antibody lacking known endogenous targets in humans. (This study has been registered at ClinicalTrials.gov under registration no. NCT02528903.).

Lim JJ ，Derby MA ，Zhang Y ，Deng R ，Larouche R ，Anderson M ，Maia M ，Carrier S ，Pelletier I ，Girard J ，Kulkarni P ，Newton E ，Tavel JA ... -  《-》

A Phase 2 Randomized, Double-Blind, Placebo-Controlled Trial of MHAA4549A, a Monoclonal Antibody, plus Oseltamivir in Patients Hospitalized with Severe Influenza A Virus Infection.

For patients hospitalized with severe influenza A virus infection, morbidity and mortality remain high. MHAA4549A, a human monoclonal antibody targeting the influenza A virus hemagglutinin stalk, has demonstrated pharmacological activity in animal studies and in a human influenza A challenge study. We evaluated the safety and efficacy of MHAA4549A plus oseltamivir against influenza A virus infection in hospitalized patients. The CRANE trial was a phase 2b randomized, double-blind, placebo-controlled study of single intravenous (i.v.) doses of placebo, 3,600 mg MHAA4549A, or 8,400 mg MHAA4549A each combined with oral oseltamivir (+OTV) in patients hospitalized with severe influenza A virus infection. Patients, enrolled across 68 clinical sites in 18 countries, were randomized 1:1:1. The primary outcome was the median time to normalization of respiratory function, defined as the time to removal of supplemental oxygen support to maintain a stable oxygen saturation (SpO2) of ≥95%. Safety, pharmacokinetics, and effects on influenza viral load were also assessed. One hundred sixty-six patients were randomized and analyzed during a preplanned interim analysis. Compared to placebo+OTV, MHAA4549A+OTV did not significantly reduce the time to normalization of respiratory function (placebo+OTV, 4.28 days; 3,600 mg MHAA4549A+OTV, 2.78 days; 8,400 mg MHAA4549A+OTV, 2.65 days), nor did it improve other secondary clinical outcomes. Adverse event frequency was balanced across cohorts. MHAA4549A+OTV did not further reduce viral load versus placebo+OTV. In hospitalized patients with influenza A virus infection, MHAA4549A did not improve clinical outcomes over OTV alone. Variability in patient removal from oxygen supplementation limited the utility of the primary endpoint. Validated endpoints are needed to assess novel treatments for severe influenza A virus infection. (This study has been registered at ClinicalTrials.gov under registration no. NCT02293863.).

Lim JJ ，Nilsson AC ，Silverman M ，Assy N ，Kulkarni P ，McBride JM ，Deng R ，Li C ，Yang X ，Nguyen A ，Horn P ，Maia M ，Castro A ，Peck MC ，Galanter J ，Chu T ，Newton EM ，Tavel JA ... -  《-》