TABLE 4.

MMR Protective Antibody Levels

Antibody	MMR Before Randomized Treatment?	Visit	Number (%) of Participants With Protective Antibody Levels
			HU	Placebo	P (Fisher’s exact test)
Measles	Yes	2–10 wk after MMR	23/24 (95.8)	10/11 (90.9)	.536
		Age 24 mo	40/40 (100.0)	31/31 (100.0)	—
		End of study	36/36 (100.0)	28/29 (96.6)	.446
	No	2–10 wk after MMR	10/14 (71.4)	24/24 (100.0)	.014
		Age 24 mo	18/19 (94.7)	28/28 (100.0)	.404
		End of study	21/21 (100.0)	27/27 (100.0)	—
Mumps	Yes	2–10 wk after MMR	23/24 (95.8)	9/11 (81.8)	.227
		Age 24 mo	40/41 (97.6)	27/31 (87.1)	.158
		End of study	37/38 (97.4)	26/29 (89.7)	.308
	No	2–10 wk after MMR	11/14 (78.6)	22/24 (91.7)	.337
		Age 24 mo	19/21 (90.5)	28/29 (96.6)	.565
		End of study	19/21 (90.5)	28/30 (96.7)	.561
Rubella	Yes	2–10 wk after MMR	24/25 (96.0)	10/13 (76.9)	.107
		Age 24 mo	36/36 (100.0)	24/24 (100.0)	—
		End of study	33/33 (100.0)	22/22 (100.0)	—
	No	2–10 wk after MMR	10/15 (66.7)	23/25 (92.0)	.081
		Age 24 mo	15/16 (93.8)	26/26 (100.0)	.381
		End of study	17/18 (94.4)	26/26 (100.0)	.409

HU, hydroxyurea.

No P value calculated (—) when hydroxyurea and placebo % protected = 100%.