Table 4.

Comparison of patients enrolled in observational studies and the AFFIRM trial

Reference	Country/no. centers	No. patients	Duration of treatment	Mean ARR in year prior to treatment	Mean baseline EDSS
Putzki et al. [8]	Germany and Switzerland/5	97 (six previously untreated)	≥12 months	2.3	3.4
Oturia et al. [9]	Denmark/2	234 (175 after switching from DMT, 45 switching from mitoxantrone, 14 treatment naïve)	Median 11.3 months (range 3–21.5 months)	2.53	4.0a
Sangalli et al. [10]	Italy/3	285 (233 after switching treatment, 52 treatment naïve)	Up to 2 years	2.13	Not reported
Outteryck et al. [12]	France/not statedb	384 (5.6% treatment naïve; efficacy data for 127)	≥12 months	2.19	3.53
Prosperini et al. [11]	Italy/1	190 (efficacy data for 169)	Median 15 (range 1–29 months)	2.0	3.4a
Mancardi et al. [15]	Italy/164	2,971	–	–	–
Putzki et al. [16]	Switzerland/3	85 (after failure of DMT)	Median 17.2 (range 12–31.4 months)	2.0	3.1
Piehl et al. [17]	Sweden/36	1,115	Mean 22 months	–	3.86c
Fernández et al. [18]	Spain/1	77	Mean 14.7 months	0.96	3.18
Horga et al. [19]	Spain	112	Mean 15.8 months	2.25	4.0
Fernández et al.d	Spain/86	1,415	Median 16 (range 1–50)	2.23	3.23
AFFIRM/Polman et al. [4]	Multinational/99	627 (natalizumab)	2 years	1.53 (natalizumab)	2.53
		315 (placebo)		1.50 (placebo)

ARR annualized relapse rate, DMT disease-modifying therapy, EDSS Expanded Disability Status Scale

^aMedian

^bData reported for two regions

^cFor the 363 patients who completed 24 months of treatment

^dThis study