Slingshot Insights

Clinical Data Update on Nov 1 2017:

9 patients with severe SCD have received LentiGlobin drug product (DP). All successfully underwent bone marrow harvest (median 2 harvests, range 1-3) to collect the stem cells used to produce LentiGlobin drug product.
Patients in this study are divided into three cohorts: A, B and C. Patients in Group A were treated under the original study protocol. Patients in Group B were treated under an amended study protocol that included changes intended to address drug product vector copy number (VCN) and engraftment challenges seen in Group A. Patients in both Group A and B had drug product made from stem cells collected using bone marrow harvest. Group C will be composed of patients treated under the amended study protocol and with drug product made from stem cells collected using apheresis with plerixafor rather than via bone marrow harvest.
7 patients were treated in Group A; initial results in these patients were presented at ASH 2016. The median cell dose was 2.1 (1.8-5.1) x 106 CD34+ cells/kg, median DP VCN was 0.6 (0.3-1.3) copies/diploid genome, and 8%-42% CD34+ cells were transduced. As of the data cutoff:
- Median follow-up was 18.3 (14.9-23.8) months since LentiGlobin infusion
- Median VCN in peripheral blood was 0.1 (0.1-0.2) copies/genome and median HbAT87Qlevel was 0.9 (0.4-2.4) g/dL at last measurement.
- Patients experiencing multiple vaso-occlusive crises (VOCs) prior to study entry (n=6; median annualized frequency 4, range 2-28 VOCs annually) have had numerically fewer VOCs since LentiGlobin DP infusion (median annualized frequency 1, range 0-24 annually, 14%-100% reduction).
2 patients were treated in Group B. As of the data cutoff:
- Patient 1313, whose DP VCNs were reported at ASH 2016, was treated with two DP lots, one of which was manufactured using the original process, and the other using the refined process.
  - The total DP cell dose was 2.2 x 106 CD34+ cells/kg. DP VCNs were 1.4 (old process) and 3.3 (refined process) copies/genome. 46% (old process) and 83% (refined process) of CD34+ cells were transduced.
  - VCN in peripheral blood was 0.5 copies/genome and HbAT87Q level was 1.5 g/dL at 3 months after LentiGlobin infusion
- Patient 1312 was treated with two DP lots manufactured using the refined process.
  - The total DP cell dose was 3.2 x 106 CD34+ cells/kg. DP VCNs were 5.0 and 2.9 copies/genome. 95% and 90% of CD34+ cells were transduced.
  - VCN in peripheral blood was 2.6 copies/genome at 1 month after LentiGlobin infusion.
  - HbAT87Q was not yet available at time of data cut for abstract
Additional patients have been enrolled in HGB-206, and data including mobilization results and DP characteristics for these patients will also be presented at ASH.

The toxicity profile observed from start of conditioning to latest follow-up was consistent with myeloablative conditioning with single-agent busulfan.

Catalyst

Do you think this event is important to the companies below? How will it affect their stock price?

Additional Information

Slingshot Insights Explained