The trading halt will remain in place until the start of normal trading on Thursday, October 10, or when an announcement is made to the market, whichever occurs earliest.
Zelda's shares last traded at 7.8 cents up from 4 cents at the start of the financial year with a new 12-month high of 9.2 cents reached on July 29.
Autism treatment cannabis study
The company marked a major milestone in August after enrolling its 103rd patient in the behavioural study evaluating medicinal cannabis treatment in children on the autism spectrum.
Children are aged about 10-years-old, diagnosed with autism and range in autism levels from classifications of low to medium or high severity.
The study is being undertaken at the Children’s Hospital of Philadalphia (CHOP) where a number of cannabis treatments are being trialled.