Background Although the use of a biologic as monotherapy is not the standard in Rheumatoid Arthritis (RA), it concerns around a third of the patients. The objectives of the Act Solo study was to evaluate tocilizumab (TCZ) alone (Mono) or in combination (Combo) at 12 months in real life.
Methods Prospective, multicenter, longitudinal, non-interventional 12-month study in RA pts requiring TCZ according to their physician. Besides drug retention rate, efficacy and safety, the effect of Mono when compared to Combo was evaluated using a propensity score. Efficacy population was pts fulfilling inclusion and non-inclusion criteria and with ≥1 TCZ infusion. Safety population was all pts with ≥1 TCZ infusion.
Results 608 pts were recruited of whom 603 were analysed for safety and 577 (Total) for other endpoints. At baseline: mean age 57±13 years, 454 (79%) females, at least 1 co-morbidity: 409 (71%), mean RA duration 11±9 years, RF or ACPA positive: 478 (86%), erosive disease: 435 (77%), mean DAS28 5.2±1.3. Past RA treatments included DMARDs + biologics in 75%, only DMARDs in 24%. MTX was previously prescribed in 95% of pts and in 71% within the last 2 years. TCZ Mono was initiated in 228 (40%) pts and TCZ Combo in 349 (60%) pts of whom 80% received MTX (mean 16±5mg/w). Steroids (GCs) were used in 386 (67%) pts (mean 10±7mg/d). 337 pts completed M12 visit. 194 pts withdrew for: AE 53 pts, inefficacy 88, patients wish 12, lost to follow-up 23, other 18. At M12, drug retention rate was 69% in Total, 67% in Mono, 71% in Combo (Fig.). Mean number of TCZ infusions was 9.4±4.1; mean time between infusions was 31.8 ±12.6 days. 29% of the pts experienced at least 1 discontinuation, 25% and 33% in Mono and Combo groups respectively. DMARD was added in 20 Mono and definitely stopped in 25 Combo pts. 170 (50%) pts remained on GCs, 66 (51%) in Mono group and 104 (50%) in Combo group. At M12, mean DAS28 in Total, Mono and Combo were 2.4±1.3, 2.4±1.3 and 2.3±1.2 respectively. DAS28 remission was 35% in Total, 35% and 36% in Mono and Combo respectively (p=0.83). Using the propensity score, no effect of Mono was observed on drug retention HR=1.194 [0.852,1.673], p=0.30; DAS remission OR=1.111 [0.773,1.597], p=0.57; or GCs use OR=0.880 [0.558,1.387], p=0.58 at M12.
No new safety signal was reported. 325 (54%) patients had at least one AE, 74 (12%) had at least one serious AE with no differences between Mono and Combo.
Conclusions The Act Solo study confirms, in real life, the clinical results of RCTs showing a comparable efficacy of TCZ as monotherapy when compared to combotherapy. No new safety signal occurred.
Disclosure of Interest J. Tebib: None declared, I. Idier Employee of: Chugai Pharma France, M. Coudert: None declared, J.-F. Maillefert: None declared, R.-M. Flipo Consultant for: Roche SAS and Chugai Pharma France