Treatment of Rett Syndrome With Recombinant Human IGF-1

What Was Tested

In this phase 2 trial, researchers set out to test IGF-1 LR3 and Mecasermin (rhIGF-1).

It had two arms (groups): Treatment Period 1 (active comparator) and Treatment Period 2 (placebo comparator).

One half of subjects will be randomly assigned to receive Recombinant Human Insulin Growth Factor 1 (rhIGF-1) , and the other half of subjects will be randomly assigned to receive placebo.

Subjects that initially received Recombinant Human Insulin Growth Factor 1 (rhIGF-1) will now receive placebo, and subjects that initially received placebo will now receive Recombinant Human Insulin Growth Factor 1 (rhIGF-1).

The registry classes the interventions as drug.

More on the Plan

Enrolled subjects will complete five study periods: screening, two 20-week long treatment periods, a 28-week break between treatment periods ("washout"), and a follow-up phone call 4 weeks after all treatment ends.

Subjects will be chosen at random to receive either IGF-1 or placebo during the first treatment period and then switch to the alternate medication for the second treatment period.

Therefore, by completion of the trial, all subjects will have received treatment with IGF-1 for 20 weeks.

The study will be double-blinded; meaning, neither subjects' families nor study investigators will know who is receiving IGF-1 or placebo at any time.

Who Took Part

The registry lists 30 actual participants took part.

It was open to women only aged from 2 years up to 10 years.

Healthy volunteers were not accepted; participants needed the condition being studied.

Examples of who could join: Genetic documentation of MECP2 mutation. Subject must be post-regression (Hagberg Stage 2). Subject and caregiver's primary language must be English. Subject must reside in North America (US and Canada). Caregiver must have internet access and be able to complete questionnaires online and communicate via email.

The full record lists 8 inclusion and 6 exclusion criteria; among the exclusions: severe scoliosis (curvature \>40 degrees); bone-age greater than 11 years; cardiomegaly (enlarged heart).

How the Study Was Run

The set-up was randomized, crossover and triple-blind.

Because people in this IGF-1 LR3 study were split into groups at random, differences between the groups are less likely to reflect who happened to join each one.

Each person switched between IGF-1 LR3 and the comparison at some point, usually with a gap in between.

As a double-blind IGF-1 LR3 study, the assignments were hidden from both participants and investigators until the end.

Those kept unaware of assignments: participant, care provider and investigator.

It started in 2013-01 with completion listed for 2016-07.

It ran at 1 site in United States.

Its stated primary purpose is treatment.

What Was Measured

Primary outcome: Anxiety, Depression, and Mood Scale (ADAMS) - Social Avoidance Subscale (time frame: Every 5 weeks during each of the two 20-week treatment periods, and once 4 weeks after final treatment ends). Clinical Global Impression - Severity (CGI-S) (time frame: Every 10 weeks during each of the two 20-week treatment periods). Parental Global Impression - Severity (PGI-S) (time frame: Every 5 weeks during each of the two 20-week treatment periods, and once 4 weeks after final treatment ends).

It also tracked 7 secondary outcomes, for example Anxiety, Depression, and Mood Scale (ADAMS), Mullen Scales of Early Learning (MSEL), Vineland Adaptive Behavior Scales, Second Edition (VABS-II), Communication and Symbolic Behavior Scales - Developmental Profile (CSBS-DP), Aberrant Behavior Checklist - Community Edition (ABC-C) and Quantitative Measures of Respiration: Apnea Index.

What This Means in Plain Language

Put simply, this is a phase 2, randomized trial of IGF-1 LR3 and Mecasermin (rhIGF-1) in 30 people.

Its size is small, so on its own it can only give an early look.

The trial is marked completed; results are posted on the registry, and this page does not restate them.

More context: the IGF-1 LR3 compound page and the Mecasermin (rhIGF-1) compound page, all human trials.