HI-E Response Assessment

Proposed IWG 2018 procedures for supporting accurate response assessment: HI-E¹⁶⁸

Item	Proposed IWG 2018 procedures
Baseline assessment Evaluation of transfusion burden & baseline Hb	16-week period* in lower risk MDS, off active treatment Transfusions: for unexpected changes in transfusion requirements, assess for confounding factors Hb: Mean pre-transfusion Hb level during screening, measurements at least 7 days apart, preferably from 1 device or laboratory Baseline Hb should be <10g/dL for therapy
Response evaluation
Evaluation period	24 weeks
Frequency	Hb measurement at least every 2 weeks during first 16 weeks of treatment
Blood count device/laboratory	See above
Dose adjustment for high Hb	If 2 subsequent measurements exceed a predefined threshold, continue treatment at a lower dose or longer interval Hb decreases from dose reduction should not be counted as loss of response Monitor blood counts at an appropriate interval

*For lower risk MDS where anemia is the prominent cytopenia. For severe thrombocytopenia, a shorter screening period may suffice; **Duration of >16 weeks is clinically meaningful; †Using the same transfusion policy; ‡Compared with 16 weeks prior to start of therapy; § Only transfusions for Hb <9g/dL are taken into account; ¶ Baseline <100 (x10⁹/L), increments for patients with baseline >100 (x10⁹/L) should also be reported; evolution of bleeding symptoms should be reported; #2 subsequent platelet counts >450 on TPO and TPO should be stopped; declines in platelet count following dose reductions or interruptions should not be considered loss of response; †† Baseline >1.0 (x10⁹/L), increases are also to be reported.
HI-E, hematologic improvement erythroid; HI-N, hematologic improvement neutrophil; HI-P, hematologic improvement platelet; HTB, high transfusion burden; IWG, International Working Group; LTB, low transfusion burden; MDS, myelodysplastic syndrome; NTD, not transfusion dependent; RBC, red blood cell; U, units.
Modified from 168.