Abatacept in subjects who switch from intravenous to subcutaneous therapy: results from the phase IIIb ATTUNE study.
OBJECTIVE
To assess safety, immunogenicity and efficacy in rheumatoid arthritis (RA) patients switched from long-term intravenous to subcutaneous (SC) abatacept.


METHODS
In this phase IIIb, open-label, single-arm trial, patients who completed ≥4 years of intravenous abatacept (in long-term extensions of two phase III studies) were enrolled to receive SC abatacept (125 mg/week). The primary objective was safety during the first 3 months after switching from intravenous therapy.


RESULTS
123 patients entered the study (mean Disease Activity Score 28 (based on C reactive protein) and HAQ-DI of 3.4 and 0.94, respectively). At month 3, 120 (97.6%) patients were continuing to receive SC abatacept; no patients discontinued due to lack of efficacy. Adverse events (AEs) were reported in 49 (39.8%) patients through month 3. One patient (0.8%) discontinued due to an AE and one patient (0.8%) experienced a serious AE. Two (1.6%) patients had SC injection site reactions (erythema, pain), both with mild intensity. Clinical efficacy was maintained throughout. Limited impact on immunogenicity was observed when switching routes of administration.


CONCLUSIONS
These data demonstrate that patients can switch from long-term monthly intravenous abatacept to a weekly fixed dose of 125 mg SC abatacept with no increased safety concerns. This study further supports SC abatacept as an alternative treatment option for patients with RA.
Rheumatology Department, Mount Sinai Hospital, Toronto, Canada. edkeystone@mtsinai.on.ca
Edward Clark
EC
Keystone
Joel M
JM
Kremer
Anthony
A
Russell
Jane
J
Box
Carlos
C
Abud-Mendoza
Mario Garza
MG
Elizondo
Allison
A
Luo
Richard
R
Aranda
Ingrid
I
Delaet
Rene
R
Swanink
Sheila
S
Gujrathi
Michael
M
Luggen
D000069594:Abatacept; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage; D000328:Adult; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage; D018501:Antirheumatic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D001172:Arthritis, Rheumatoid / Q000188:drug therapy* / Q000276:immunology / Q000473:pathology; D002097:C-Reactive Protein / Q000378:metabolism; D004359:Drug Therapy, Combination; D005500:Follow-Up Studies; D006801:Humans; D018796:Immunoconjugates / Q000008:administration & dosage* / Q000009:adverse effects; D007275:Injections, Intravenous; D007279:Injections, Subcutaneous; D007596:Joints / Q000187:drug effects* / Q000473:pathology; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D013995:Time; D016896:Treatment Outcome
D000305:Adrenal Cortex Hormones; D000894:Anti-Inflammatory Agents, Non-Steroidal; D018501:Antirheumatic Agents; D018796:Immunoconjugates; D000069594:Abatacept; D002097:C-Reactive Protein