Is SGMO falling behind?
"I was previously very skeptic about AVROBIO’s (AVRO) Fabry program (AVR-RD-01) given the decline in enzyme (AGA) levels and VCN seen 3-6 months post treatment. Based on the trajectory at the time I thought transduced cells will eventually vanish after ~2 years which could make AVR-RD-01 irrelevant.
I am now much more optimistic following last month’s update that demonstrated stabilization of the slope of AGA levels and VCN in two patients 18 and 28 months post treatment, respectively (three additional patients did not have long enough follow up).
While more data are needed (# of patients and longer follow up) the new data suggests AVR-RD-01 may have a long lasting “tail” of enzyme activity. Enzyme levels generated by AVR-RD-01 appear clinically meaningful based on substrate reduction to levels below what had been achieved with ERT in these patients. Importantly, patient #1 is ERT free for 10 months with no significant changes in substrate levels, which unequivocally demonstrates the treatment’s activity with ERT’s “masking” effect." http://www.orf-blog.com/portfolio-updates-adc-data-readouts-avrobio-chiasma