Eventual response to alemtuzumab therapy according to log depletion in absolute B-cell count from week 2 to week 4 for patients with a week-2 B-cell count greater than 0.001 × 109/L
. | No. of patients (%), according to response . | . | . | . | |||
|---|---|---|---|---|---|---|---|
| Log depletion . | < 3 . | < 2 . | < 1 . | < 0 . | |||
| NR | 25 (93) | 22 (81) | 15 (56) | 2 (100) | |||
| PR/CR | 10 (71) | 4 (29) | 1 (7)* | 0 (0) | |||
. | No. of patients (%), according to response . | . | . | . | |||
|---|---|---|---|---|---|---|---|
| Log depletion . | < 3 . | < 2 . | < 1 . | < 0 . | |||
| NR | 25 (93) | 22 (81) | 15 (56) | 2 (100) | |||
| PR/CR | 10 (71) | 4 (29) | 1 (7)* | 0 (0) | |||
The majority of nonresponding patients can be identified by the difference in B-cell levels from week 2 to week 4. Patients with a week 2 B-cell count greater than 0.001 × 109/L, who show less than one order of magnitude depletion over the next 2 weeks of therapy, show no response to therapy beyond week 4. Partial responders generally show a 1 to 2 log depletion in circulating B-cell count from week 2 to week 4. Only one PR+ patient (*) showed less than one log depletion, but this patient had a maximum response at week 4. Complete responders usually have less than 0.001 × 109/L B cells by week 2, but if not they generally show a 2 or 3 log depletion of circulating B cells from week 2 to 4. NR, n = 27; PR/CR, n = 14.