Table 1.

Characteristics of patients and the infused patient-autologous gene therapy products^(a)

	P1	P2	P3	P4	P5	P6	P7
Age at GT (years or months)	10 years	15.5 years	10 years	10 months	3 years	7 years	3.5 years
WAS Gene mutation	401C/T p.A134V	c.1453+1 G>C	c.628delT p.S210HfsX51	c.1295delG p.G432EfsX13	c.257G>A p.R86H	100C>T p.R34X	1271dup(ex10) Leu425Profsx70
Revertant cells	−	+	+	−	−	+	−
Mutant WASp expression	+	−	−	−	−	−	+
Clinical manifestations, in the 2 years preceding GT(b)
Bleeding(c)	Bruising	Severe Splenectomized	Severe Splenectomized Multiple platelet transfusions	Severe Multiple platelet transfusions	Severe Multiple platelet transfusions; N-plate	Bruising (moderate)	Severe Multiple Platelet transfusions; N-plate
Eczema	Severe	Severe	Mild	Mild	Severe	Severe	Severe
Infections	Severe	2 episodes of sepsis, severe VZV	Severe chronic VZV, HSV, CMV, EBV infections	Mild	Mild	Severe	Gastroenteritis (2 episodes)
Autoimmunity	Recurrent arthritis Renal Disease	Severe lower limbs vasculitis and arthritis, unable to walk	Pancytopenia	Severe Thrombocytopenia Mild skin vasculitis	Severe Thrombocytopenia	None	Severe Thrombocytopenia Mild cutaneous vasculitis
Days in hospital for disease-related complications	<5	47days	>6 months	26 days(b) (in 10 months)	19 days	<5	21days
Clinical score(d)	5	5	5	5	5	3	5
Date of GT	March/03/2011	May/27/2011	Nov/18/2011	April/20/2012	June/15/2012	Nov/16/2012	January/24/2014
HSC origin	BM	MPB	MPB	BM	BM	BM	MPB
Total CD34+ cell dose ×106/kg	2	11	11	7.3	6.8	3.1	15
VCN	0.7	1.3	1.2	2.8	0.6	1.7	0.6
Date of last Fup	Nov/12/2014	May/28/2014	Death July/11/2012	Oct/04/2014	June/11/2014	Nov/12/2014	Nov/03/2014
Fup (months)(d)	42	36	7	30	24	24	9
Clinical status 2 years post GT or at last Fup	A&W	A&W	Died of opportunistic viral infections	A&W	A&W	A&W	A&W
Bleeding	Bruising (resolved after splenectomy)	No	NA	Bruising	Bruising	Bruising (mild)	Bruising
Eczema	No	Very mild	NA	No	No	No	No
Infections	No	Localized zoster (1 episode)	NA	No	Mild gastroenteritis (1 episode)	No	No
Autoimmunity	No	Mild vasculitis, able to walk	NA	No	No	No	No
Days in hospital (post initial GT period), over following 2 years	0	5	Continuous hospitalization until death	0	5	0	0(d)
Clinical score at last Fup	<1	5 (mild autoimmunity)	NA	<1	<1	<1	1

^(a)P1 and P6 were included in London, and P2, P3, P4, P5 and P7 were included in Paris; P: patient; GT: gene therapy; HSC: hematopoietic stem cells; BM: bone marrow; MPB: mobilized peripheral blood; VCN: vector copy number per cell in cultured transduced CD34+ cells; Revertant cells are detected in blood and have recovered some expression of WASp as a result of selected spontaneous somatic mutations; Fup: Follow-up; A&W: alive and well; NA: not applicable; Severe eczema is defined by intense redness, thickness/swelling, and may include diffuse or superinfected lesions; Severe infection indicates infections requiring hospitalization and parenteral treatment ; Severe thrombocytopenia is defined as platelet counts below 10,000/mm³.

^(b)P4 had a shorter period of observation since he was treated at the age of 10 months

^(c)Thrombocytopenia was initially below 20,000/mm³ in P1, P2, P3 and P6 and below 10,000/mm³ in P4, P5 and P7. P2 and P3 were splenectomized prior to GT. P1 was successfully splenectomized after GT

P3, P4, P5 had more than 20 platelet transfusions, P7 more than 10, P5 and P7 received additional N-plate therapy.

^(d)P7 has a shorter follow up of 9 months.

“+” Revertant cells and mutant protein are present and detectable in blood cells

“−” Revertant cells and mutant protein are absent and not detectable in blood cells