Anavex Life Sciences on Tuesday touted the effect its treatment had on patients with Rett syndrome, but AVXL stock crashed following what Chief Executive Christopher Missling called "an inaccurate impression."
A third-party website called ClinicalTrials.gov shows Anavex changed the goal posts on its test — and the actual phase of the study — just two weeks ago. But Missling says the changes were implemented in December. The website was updated late.
"The administrative updates on the website were not made on a timely basis by the CRO (clinical research organization), leaving the inaccurate impression of a late change, which was actually not the case," Missling told Investor's Business Daily.
Still, AVXL stock toppled 15.6% to 11.04 during the regular session on the stock market today. After the close, shares ticked up 2.1% near 11.30.
AVXL Stock: December Changes
In the best case, a late change to a study's design could cloud the drug's actual benefit for patients. In the worst case, it leaves the impression that a company changed the goals when the drug was actually underperforming the prespecified measures.
Neither was the case here, Missling says. ClinicalTrials.gov published the changes on Jan. 18.
The company studied its drug in patients with Rett syndrome, a neurological disorder that appears almost exclusively in females. The disease is caused by a genetic mutation that affects a person's ability to speak, walk, eat and breathe.
In the study, the drug led to a statistically significant improvement in behavioral symptoms, measured by a scale specific to the disease. Anavex described the effect as "very large." The drug also led to "large" improvement in emotional behavioral symptoms on a second scale.
Missling says Anavex selected those two measures — respectively, the Rett Syndrome Behavioral Questionnaire and the Anxiety, Depression and Mood Scale — in December. The decision took place after all the patients were enrolled but before Anavex had any data on the drug's performance.
"The misunderstanding was the information of the upgrade of the trial was done to this website at a late stage, giving the wrong impression that (the changes were) done at a late time," Missling said. As a result, AVXL stock took a beating on Tuesday.
The company also decided then to upgrade the study to a Phase 3 test based on confidence in earlier studies, Missling said. The new measures selected offer a better look at the drug's benefit, he said.
Missling noted the company described the test as potentially "pivotal" at the J.P. Morgan Healthcare Conference in early January. The company's presentation from the conference references the study as a Phase 2 and Phase 3 test.
Rett Syndrome Test
More than seven in 10 patients — roughly 72% — who received Anavex's drug improved on the Rett Syndrome Behavioral Questionnaire. Nearly 39% of placebo patients showed a similar improvement.
On a secondary measure — known as Anxiety, Depression and Mood Scale — nearly 53% of patients on Anavex's drug improved. Meanwhile, just north of 8% of placebo patients showed improvement.
Previously, Anavex planned to measure the concentration of its drug in patients' plasma at seven weeks. It also planned to look at behavioral measures on the same Rett Syndrome Behavioral Questionnaire and another called the Clinical Global Impressions Scale.
Follow Allison Gatlin on Twitter at @IBD_AGatlin.
