Joseph J. Hlavka

Double-blind, placebo-controlled study of INN 00835 (netamiftide) in the treatment of outpatients with major depression.

This study was designed to determine the safety, efficacy and pharmacokinetics of the antidepressant netamiftide (previously designated name: INN 00835) after 5 or 10 daily doses administered to patients diagnosed with major depression. Netamiftide was administered subcutaneously at a fixed dose of 18 mg/patient per day. Of the 55 enrolled patients, 22 were dosed for 10 days with drug, 11 for 5 days with drug followed by 5 days with placebo and 22 for 10 days with placebo only. The effect of treatment with netamiftide was evaluated by the following psychometric tests: Hamilton Depression Rating, Montgomery-Asberg Depression Rating Scale, Carroll Self-Rating Depression and Clinical Global Impression scales. None of the patients experienced significant adverse effects. A pharmacodynamic correlation (P < 0.05) was found between plasma drug concentrations and response to treatment. Highest plasma concentrations (Cmax) of netamiftide averaging 45.7 ng/ml were observed at 0.25 h after dosing. There were 89% responders in the group with Cmax ≥ 45.7 ng/ml (minimum therapeutic concentration) versus 40% in the group with Cmax < 45.7 ng/ml. Onset of action was observed within 48 h after treatment, peak effect was observed at approximately 1 week after treatment and efficacy lasted during a 4-week follow-up period. Netamiftide is a promising antidepressant with rapid onset of action and with an excellent safety profile.

Efficacy and safety of 30 mg/d and 45 mg/d nemifitide compared to placebo in major depressive disorder

Nemifitide is a novel pentapeptide antidepressant, which appears to be effective in the treatment of major depressive disorder (MDD). In the present study 81 patients with MDD, DSM-IV criteria were randomized following a 1-wk screening period to receive 30 mg/d nemifitide, 45 mg/d nemifitide or placebo in a 6-wk double-blind, multicentre, outpatient efficacy study. Nemifitide or placebo was delivered by subcutaneous injection for 2 wk daily for 5 days (Monday to Friday) in the first 2 wk and patients were followed up for a further 4 wk. The primary efficacy measure was the change from baseline on the Montgomery-Asberg Depression Rating Scale. Secondary measures included the 17-item Hamilton Psychiatric Rating Scale for Depression (HAMD), the CGI severity and improvement scale and the Carroll Self-Rating Scale for Depression. This proof-of-principle study demonstrated a statistically significant superiority of the 45-mg/d dose vs. placebo at the time-point of peak effect (1 wk after the end of treatment). There appeared to be a greater effect with the 45 mg/d nemifitide dose than with 30 mg/d. An additional exploratory analysis by stratification of all patients by severity above and below or equal to the median baseline HAMD score of 22 showed a higher percentage of responders for both doses of nemifitide with statistical separation from placebo for patients with baseline HAMD score of >22 (above the median). There was no significant difference among treatment groups for patients with baseline HAMD score of <or=22. Nemifitide showed a good tolerability and safety profile. There were no dropouts due to adverse events, and the incidence of side-effects with nemifitide was comparable with that of placebo.

Clinical effectiveness of nemifitide, a novel pentapeptide antidepressant, in depressed outpatients: comparison of follow-up re-treatment with initial treatment.

Data from two Phase 2 clinical studies with nemifitide, a novel pentapeptide antidepressant, were evaluated. The initial double-blind, placebo-controlled study was performed on outpatients with DSM-IV criteria for major depressive disorder. An open-label extension study enrolled subjects either completing or having been discontinued due to lack of efficacy during the follow-up period of the initial study. In the extension study, both the investigator and the subjects were blinded to the previous treatment in the initial study. No clinically significant side-effects were observed in either study. Twenty-seven subjects have been entered and evaluated in the extension study. Eighteen of these 27 subjects (66.7%) responded to re-treatment in the extension study. Mean duration of effect between re-treatments was 3.3 months. The results of the extension study support investigating a range of doses of nemifitide from 18 to 72 mg/d in future clinical trials. Further studies are planned to determine the most effective nemifitide clinical treatment regimen.

Clinical effect of nemifitide, a novel pentapeptide antidepressant, in the treatment of severely depressed refractory patients.

Clinical data were evaluated from an open-label, single-center, pilot study in patients with chronic refractory depression. The primary efficacy criterion was the change from baseline using the Montgomery–Asberg Depression Rating Scale. The secondary efficacy criteria were the 17-item Hamilton Depression Rating Scale and the Clinical Global Impression-Improvement scale. Response to treatment (40–240 mg once per day by subcutaneous injection for 10–20 doses) was defined as more than 50% improvement in the Montgomery–Asberg Depression Rating Scale from baseline or Clinical Global Impression-Improvement ≤2 and lasting for at least two sequential weeks. Patients with a sustained response at the end point in the acute main treatment phase were enrolled for up to 2 years in a maintenance phase of the study to determine duration of response and to initiate retreatments upon relapse. Of the 25 patients with chronic refractory depression, 11 patients showed a response for Montgomery–Asberg Depression Rating Scale and one responded according to the secondary criterion Hamilton Depression Rating Scale. In seven of the 11 responders to Montgomery–Asberg Depression Rating Scale the effects were sustained for the remainder of the acute phase. Two additional sustained responders identified according to secondary criteria (Hamilton Depression Rating Scale or Clinical Global Impression-Improvement) were also enrolled in the maintenance phase. All nine sustained responders were retreated, as needed, in the maintenance phase of the study, ranging from 71 to 660 days. Mean duration of response following initial treatment and between retreatments was around 2 months. Pharmacokinetic data indicated dose-proportional systemic exposure to the drug.