AAV8 doing its job

There has been speculation in some quarters that the AAV8 vector used for TT-034 may not be an efficient vector. We will soon know the real answer to this question. However, in between time, results from other trials using AAV8 could be a guide to the possible outcome for TT-034.

Earlier this week, Baxter released some preliminary results from its haemophilia B trial. This trial uses AAV8 in a dose escalation study. It started recruiting at about 10 US sites in early 2013. By the end of 2014, 6 patients had been treated in 3 cohorts. So far, only one patent has had in immune response and that patient was treated with oral corticosteroids. That patient was one of those administered with the highest dose to-date.

There is clearly more work being done as the highest doses in the trial (the last ten patients) are yet to be administered. These results are, therefore, not final but they tend to suggest that the AAV8 vector is doing its job in the liver.

The vector that Baxter is using is (I believe) a more refined/engineered vector than that used for TT-034 but, nevertheless, these results do indicate that a therapeutic transfection rate of the TT-034 AAV vector could be achieved. Good news in the lead up to Benitec's next announcement.