A Study of Tocilizumab in Combination With an Oral Contraceptive in Patients With Rheumatoid Arthritis

Blood samples were collected prior to the administration of Ortho-Novum® 1/35 on Day 21 of each cycle. Serum levels of progesterone were quantitatively determined using the ADVIA Centaur and ADVIA Centaur XP systems (Siemens Healthcare Diagnostics Inc., Tarrytown, NY, USA). The assay was a competitive immunoassay using direct chemiluminescent technology.

Blood samples were collected prior to and at 0.5, 1, 1.5, 2, 3, 5, 8, 12 and 24 hours after administration of Ortho-Novum® 1/35 on Day 7 of each cycle. The concentrations of ethinyl estradiol and norethindrone were determined in human heparinized plasma according to a validated gas chromatography coupled to mass spectrometry (GC-MS) method. The maximum observed plasma concentration (Cmax) was derived from the plasma concentrations using a non-compartmental method with the software WinNonlin Enterprise version 5.2 (or above).

Blood samples were collected prior to and at 0.5, 1, 1.5, 2, 3, 5, 8, 12 and 24 hours after administration of Ortho-Novum® 1/35 on Day 7 of each cycle. The concentrations of ethinyl estradiol and norethindrone were determined in human heparinized plasma according to a validated gas chromatography coupled to mass spectrometry (GC-MS) method. The time to reach the maximum plasma concentration (Tmax) was derived from the plasma concentrations using a non-compartmental method with the software WinNonlin Enterprise version 5.2 (or above).

Blood samples were collected prior to and at 0.5, 1, 1.5, 2, 3, 5, 8, 12 and 24 hours after administration of Ortho-Novum® 1/35 on Day 7 of each cycle. The concentrations of ethinyl estradiol and norethindrone were determined in human heparinized plasma according to a validated gas chromatography coupled to mass spectrometry (GC-MS) method. The area under the plasma concentration-time curve from 0 to 24 hours (AUC0-24) was derived from the plasma concentrations using a non-compartmental method and computed using the linear trapezoidal rule with the software WinNonlin Enterprise version 5.2 (or above).

Blood samples were collected prior to and at 0.5, 1, 1.5, 2, 3, 5, 8, 12 and 24 hours after administration of Ortho-Novum® 1/35 on Day 7 of each cycle. The concentrations of ethinyl estradiol and norethindrone were determined in human heparinized plasma according to a validated gas chromatography coupled to mass spectrometry (GC-MS) method. The terminal half-life (t½) was derived from the plasma concentrations using a non-compartmental method with the software WinNonlin Enterprise version 5.2 (or above).

Blood samples were collected prior to and at 0.5, 1, 1.5, 2, 3, 5, 8, 12 and 24 hours after administration of Ortho-Novum® 1/35 on Day 7 of each cycle. The concentrations of ethinyl estradiol and norethindrone were determined in human heparinized plasma according to a validated gas chromatography coupled to mass spectrometry (GC-MS) method. The apparent oral clearance (CL/F) was derived from the plasma concentrations using a non-compartmental method and computed as dose/AUC0-24 with the software WinNonlin Enterprise version 5.2 (or above).

Blood samples were collected pre-dose and at the end of infusion of tocilizumab on Day 1 of Cycle 2. Additional blood samples were collected on Days 2, 3, 5, 7, 12, 14, 21 of Cycle 2, and Days 1, 7, and 21 of Cycle 3. The concentration of tocilizumab was determined in serum samples using a validated enzyme-linked immunosorbent assay (ELISA). The maximum observed plasma concentration (Cmax) was derived from the serum concentrations using a non-compartmental method with the software WinNonlin Enterprise version 5.2 (or above).

Blood samples were collected pre-dose and at the end of infusion of tocilizumab on Day 1 of Cycle 2. Additional blood samples were collected on Days 2, 3, 5, 7, 12, 14, 21 of Cycle 2, and Days 1, 7, and 21 of Cycle 3. The concentration of tocilizumab was determined in serum samples using a validated ELISA. The time to reach maximum serum concentration was derived from the serum concentrations using a non-compartmental method with the software WinNonlin Enterprise version 5.2 (or above).

Blood samples were collected pre-dose and at the end of infusion of tocilizumab on Day 1 of Cycle 2. Additional blood samples were collected on Days 2, 3, 5, 7, 12, 14, 21 of Cycle 2, and Days 1, 7, and 21 of Cycle 3. The concentration of tocilizumab was determined in serum samples using a validated ELISA. The area under the serum concentration-time curve from 0 to infinity (AUCinf) was derived from the serum concentrations using a non-compartmental method with the software WinNonlin Enterprise version 5.2 (or above). AUCinf was computed using the linear trapezoidal rule to tlast plus Clast/Kel, where tlast is the time of the last measurable concentration, Clast is the last measurable concentration, and Kel is the apparent elimination rate, computed as the magnitude of the slope from the log-linear regression of the apparent terminal elimination phase of the serum concentration-versus-time curve.

Blood samples were collected pre-dose and at the end of infusion of tocilizumab on Day 1 of Cycle 2. Additional blood samples were collected on Days 2, 3, 5, 7, 12, 14, 21 of Cycle 2, and Days 1, 7, and 21 of Cycle 3. The concentration of tocilizumab was determined in serum samples using a validated ELISA. The terminal half-life (t½) was derived from the serum concentrations using a non-compartmental method with the software WinNonlin Enterprise version 5.2 (or above).

Blood samples were collected pre-dose and at the end of infusion of tocilizumab on Day 1 of Cycle 2. Additional blood samples were collected on Days 2, 3, 5, 7, 12, 14, 21 of Cycle 2, and Days 1, 7, and 21 of Cycle 3. The concentration of tocilizumab was determined in serum samples using a validated ELISA. Clearance (CL), computed as dose/AUCinf, was derived from the serum concentrations using a non-compartmental method with the software WinNonlin Enterprise version 5.2 (or above).

Blood samples were collected pre-dose and at the end of infusion of tocilizumab on Day 1 of Cycle 2. Additional blood samples were collected on Days 2, 3, 5, 7, 12, 14, 21 of Cycle 2, and Days 1, 7, and 21 of Cycle 3. The concentration of tocilizumab was determined in serum samples using a validated ELISA. The apparent volume of distribution (Vz), computed as CL/Kel where CL is clearance and Kel is the apparent elimination rate, was derived from the serum concentrations using a non-compartmental method with the software WinNonlin Enterprise version 5.2 (or above).

Blood samples were collected pre-dose and at the end of infusion of tocilizumab on Day 1 of Cycle 2. Additional blood samples were collected on Days 2, 3, 5, 7, 12, 14, and 21 of Cycle 2, and Days 1, 7, and 21 of Cycle 3. Serum levels of soluble interleukin-6 receptor were analyzed using a validated ELISA.

Blood samples were collected pre-dose of tocilizumab infusion on Day 1 of Cycle 2 and on Days 2, 3, 5, 7, 12, 14, and 21 of Cycle 2, and on Days 1, 7, and 21 of Cycle 3. Serum levels of C-reactive protein were measured by the Tina-quant CRP (latex) high-sensitivity Roche Immunoturbidimetric method.