Gemtuzumab ozogamicin (Mylotarg) as a single agent for molecularly relapsed acute promyelocytic leukemia.
The anti-CD33 antibody calicheamicinconjugate gemtuzumab ozogamicin (GO) was used to treat 16 patients with acute promyelocytic leukemia (APL) who had relapsed at the molecular level. Of these patients, 8 were experiencing a first, 5 a second, 2 a third, and 1 a fourth relapse. GO was administered at 6 mg/m2 for 2 doses, and patients achieving a new molecular remission (MR) (ie, negativity of the reverse transcriptase-polymerase chain reaction [RT-PCR] test for PML/RARalpha) received a third dose. MR was obtained in 9 (91%) of 11 patients tested after 2 doses and in 13 (100%) of 13 patients tested after the third dose. Of the 3 remaining patients, 1 achieved MR after one GO administration and received no further therapy owing to hepatic toxicity, and 2 showed disease progression during treatment. Quantitative RT-PCR studies showed that responding patients experienced a dramatic decline (at least 2 logs) of the PML/RARalpha transcript after the first GO dose. Of 14 responders, 7 remained in sustained MR for a median of 15 months (range, 7-31 months) while 7 experienced relapse at 3 to 15 months. GO was administered again in 2 patients with relapse, and both obtained a new MR. These data indicate that GO is highly effective as a single treatment for patients with molecularly relapsed APL including those with very advanced disease.
Lo-Coco
Francesco
F
Dipartimento di Biopatologia e Diagnostica per Immagini, Università Tor Vergata, Rome, Italy. francesco.lo.coco@uniroma2.it
Cimino
Giuseppe
G
Breccia
Massimo
M
Noguera
Nélida I
NI
Diverio
Daniela
D
Finolezzi
Erica
E
Pogliani
Enrico M
EM
Di Bona
Eros
E
Micalizzi
Concetta
C
Kropp
Mariagrazia
M
Venditti
Adriano
A
Tafuri
Agostino
A
Mandelli
Franco
F
D000293:Adolescent; D000328:Adult; D000368:Aged; D000617:Aminoglycosides / Q000627:therapeutic use*; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D000079982:Gemtuzumab; D006801:Humans; D000922:Immunotoxins / Q000627:therapeutic use*; D015473:Leukemia, Promyelocytic, Acute / Q000188:drug therapy* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012074:Remission Induction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D016896:Treatment Outcome
D000617:Aminoglycosides; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D000922:Immunotoxins; D000079982:Gemtuzumab