Following disappointing results in its gene therapy trial for haemophilia , UK - based Spark Therapeutics 's shares have fallen by 25 % . BioMarin's shares were up 6.4 percent Tuesday. Spark claims that the experimental treatment for diabetes significantly reduces the need for infusions by 97 % in a trial of 12 patients . However , in the higher dosage trial intended for later stage testing , the treatment had an negative reaction in two of seven patients , with one admitted to hospital with a serious adverse effect .
Following disappointing results in its gene therapy trial for haemophilia , UK - based Spark Therapeutics 's shares have fallen by 25 % . Spark claims that the experimental treatment for diabetes significantly reduces the need for infusions by 97 % in a trial of 12 patients . However , in the higher dosage trial intended for later stage testing , the treatment had an negative reaction in two of seven patients , with one admitted to hospital with a serious adverse effect .