A phase I study assessing the safety, clinical response, and pharmacokinetics of an experimental infliximab formulation for subcutaneous or intramuscular administration in patients with rheumatoid arthritis.
OBJECTIVE
To assess safety, clinical response, and pharmacokinetics of subcutaneous (SC) and intramuscular (IM) doses of an experimental formulation of infliximab [including experimental SC doses following administration of commercially-formulated intravenous (IV) infliximab] in patients with rheumatoid arthritis (RA) refractory to methotrexate.


METHODS
In this randomized, open-label, 3-stage design, 43 subjects were enrolled in 7 dose groups. In Stage I, 15 subjects received single SC doses of 0.5, 1.5, or 3.0 mg/kg. In Stage II, 21 subjects received one of 3 regimens: 100 mg SC every 2 weeks (3 injections); 3 mg/kg commercially-formulated IV infliximab every 2 weeks (2 infusions) followed by 100 mg SC every 2 weeks (3 injections); or 100 mg IM every 2 weeks (3 injections). In Stage III, 7 subjects received 100 mg SC every 4 weeks (3 injections).


RESULTS
No treatment-related serious adverse events were observed, and there were no serious injection site reactions. A low-titer infliximab antibody response was detected in 27% of subjects receiving single SC doses, 5% receiving multiple SC doses, and 43% receiving IM doses. SC administration yielded roughly dose-proportional increases in Cmax and AUC. American College of Rheumatology 20% response (ACR20) was achieved 2 weeks after the last injection by 86.7% of subjects receiving single SC doses, 85.7% receiving SC doses every 2 weeks, 85.7% receiving both IV and SC doses, 57.1% receiving multiple IM doses, and 80.0% receiving SC doses every 4 weeks.


CONCLUSIONS
SC and IM treatment with this experimental infliximab formulation was well tolerated and was associated with a favorable ACR response.
Westhovens
René
R
Houssiau
Frédéric
F
Joly
Johan
J
Everitt
Daniel E
DE
Zhu
Yaowei
Y
Sisco
Deborah
D
Van Hartingsveldt
Bart
B
Mascelli
Mary Ann
MA
Graham
Martin A
MA
Durez
Patrick
P
Bouman-Thio
Esther
E
D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D000917:Antibody Formation; D018501:Antirheumatic Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004351:Drug Resistance; D005260:Female; D006801:Humans; D000069285:Infliximab; D007273:Injections, Intramuscular; D007279:Injections, Subcutaneous; D008297:Male; D008727:Methotrexate / Q000627:therapeutic use; D008875:Middle Aged; D010865:Pilot Projects
D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D000069285:Infliximab; D008727:Methotrexate