Certolizumab Pegol Treatment in Axial Spondyloarthritis Mitigates Fat Lesion Development: 4-Year Post-Hoc MRI Results from a Phase 3 Study

OBJECTIVES

Fat lesions (FLs) on MRI T1 sequences are considered early indicators of structural spinal progression in axial spondyloarthritis (axSpA) patients. In this post-hoc analysis from RAPID-axSpA, we assess whether TNFi treatment over 4 years impacts FLs in spinal vertebral edges (VEs) of patients with axSpA.

METHODS

In RAPID-axSpA (NCT01087762), a 4-year, phase 3 randomised trial, participants were randomised to certolizumab pegol (CZP; 400 mg loading dose at Weeks 0/2/4 then 200/400 mg every 2/4 weeks) or placebo (PBO) at baseline; PBO-randomised participants switched to CZP at week 16/24 (denoted PBO-randomised/CZP). Spinal MRI scans were taken at Weeks 0, 12, 48, 96 and 204. Changes in proportions of VEs with FLs are reported as odds ratios (OR) between timepoints.

RESULTS

Overall, 136 participants (CZP: 89, PBO-randomised/CZP: 47) had a baseline and ≥1 post-baseline MRI. The OR (95% CI) vs baseline of FLs was higher in PBO-randomised/CZP vs CZP-randomised participants at Weeks 48 (3.35 [2.16-5.19] vs 1.45 [1.07-1.97]), 96 (2.62 [1.77-3.88] vs 1.84 [1.36-2.48]) and 204 (2.55 [1.59-4.06] vs 1.71 [1.23-2.37]). Across 204 weeks, FLs increased more in VEs with baseline inflammation (week 204 OR: 4.84 [2.56-9.18]) than those without (OR: 1.15 [0.78-1.71]). VEs in which inflammation was resolved by week 12 had lower FL prevalence at Weeks 48, 96 and 204 compared with VEs with unresolved inflammation.

CONCLUSIONS

Early and sustained suppression of inflammation mitigates the risk of long-term fat lesion development in the spine in study participants with axSpA evaluated over 4 years.

OP0104 THE IMPACT OF PERSISTENT INFLAMMATORY CHANGES ON PREVALENCE OF FATTY LESIONS IN PATIENTS WITH AXIAL SPONDYLOARTHRITIS TREATED WITH CERTOLIZUMAB PEGOL: 4-YEAR MRI RESULTS FROM RAPID-AXSPA

Background:

Axial spondyloarthritis (axSpA) is a chronic disease characterised by inflammation in the sacroiliac joints and spine, causing severe back pain and stiffness. Emerging evidence suggests chronic spinal inflammation may be associated with osteoproliferation leading to syndesmophyte formation and spinal ankylosis, with subsequent worsening of patient mobility and function.1Fatty lesions (FLs) on magnetic resonance imaging (MRI) T1 sequences are considered to be post-inflammatory precursors to these changes. Certolizumab pegol (CZP), an Fc-free, PEGylated tumour necrosis factor inhibitor (TNFi), has proven efficacy in treating the signs and symptoms of axSpA.2,3CZP has also been shown to decrease spinal and sacroiliac joint MRI inflammation, and limit radiographic progression of the spine over 4 years of treatment.4

Objectives:

To report the effect of early post-baseline (BL) inflammatory changes on fatty lesion prevalence over 4 years in a broad axSpA patient population treated with CZP.

Methods:

RAPID-axSpA (NCT01087762) was a phase 3 trial which was double-blind and placebo (PBO)-controlled to Week (Wk) 24, dose-blind to Wk 48 and open-label to Wk 204. CZP-randomised axSpA patients (Wk 0 CZP: 200 mg every 2 wks [Q2W] or 400 mg Q4W) continued their assigned dose throughout; PBO-randomised axSpA patients (Wk 0 PBO) received CZP from Wk 24, or if non-responders, from Wk 16 onwards. Blinded spinal MRI scans at Wks 0, 12, 48, 96 and 204 were assessed by 2 central readers to evaluate FL and inflammatory lesions in vertebral edges (VEs). Changes in FL prevalence are reported as odds ratios (OR; FL+/FL-) between time points or inflammation states, with nominal 95% confidence intervals (CI), for Wk 0 CZP. ORs were estimated from a logistic regression model for VE level data with random effects for patient and VE (within patient). The fixed model effects included time point, inflammatory status of VEs at BL and Wk 12, FL status at BL, and interactions if appropriate.

Results:

Of 325 axSpA patients, 89 and 47 initially randomised to CZP or PBO, respectively, had a BL and ≥1 post-BL MRI and therefore were eligible for these analyses. In these patients, a total of 3,127 of VEs were assessed at BL; inflammation was observed in 21.6% and FL in 29.3% of VEs, equating to mean counts of 5.0 and 6.7 per patient; 10.5% of VEs had both inflammation and FL at BL. At BL, FLs were relatively more often observed in inflamed VEs vs non-inflamed VEs: OR (95% CI) of 3.30 (1.94, 5.61). This difference increased over time, as the OR of FL at Wk 204 vs BL was 2.82 (1.70, 4.66) in VEs that were inflamed at BL compared with 1.08 (0.79, 1.48) in VEs that were not inflamed at BL (Figure 1A). Resolution of inflammation by Wk 12 appeared to lower the risk of FL prevalence over 4 years. When adjusted for BL VE status with respect to inflammation and FL, if inflammation prevailed at Wk 12, the OR of FL vs no FL was 1.80 (0.93, 3.49) at Wk 48, 2.54 (1.32, 4.91) at Wk 96 and 3.91 (1.87, 8.15) at Wk 204 (Figure 1B).

Conclusion:

This is the first report from a clinical interventional PBO-controlled study in a broad axSpA population showing that inflammation that prevailed after the start of TNFi treatment was associated with increased FL prevalence over 4 years. Reduction of inflammation by Wk 12 mitigated the risk of FL over the long-term, indicating the importance of early, effective and long-term treatment targeting inflammation. Similarly, a complete and persistent reduction of inflammation appears to be critical in these patients.

References:

[1]Maksymowych WP. Ann Rheum Dis 2013;72:23–8;2.Van der Heijde D. Rheumatology (Oxford) 2017;56:1498–509;3.Deodhar A. Arthritis Rheumatol 2019;71:1101–11;4.Van der Heijde D. Ann Rheum Dis 2018;77:699–705.

Acknowledgments:

This study was funded by UCB Pharma. Editorial services were provided by Costello Medical.

Disclosure of Interests:

Xenofon Baraliakos Grant/research support from: Grant/research support from: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Consultant of: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Speakers bureau: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Sebastian Kruse: None declared, Simone Auteri Shareholder of: UCB Pharma, Employee of: UCB Pharma, Natasha de Peyrecave Employee of: UCB Pharma, Tommi Nurminen Employee of: UCB Pharma, Thomas Kumke Employee of: UCB Pharma, Bengt Hoepken Employee of: UCB Pharma, Juergen Braun Grant/research support from: Abbvie (Abbott), Amgen, BMS, Boehringer, Celgene, Celltrion, Centocor, Chugai, Eli Lilly and Company, Medac, MSD (Schering Plough), Mundipharma, Novartis, Pfizer (Wyeth), Roche, Sanofi- Aventis, and UCB Pharma, Consultant of: Abbvie (Abbott), Amgen, BMS, Boehringer, Celgene, Celltrion, Centocor, Chugai, EBEWE Pharma, Eli Lilly and Company, Medac, MSD (Schering-Plough), Mundipharma, Novartis, Pfizer (Wyeth), Roche, Sanofi-Aventis, and UCB Pharma, Speakers bureau: Abbvie (Abbott), Amgen, BMS, Boehringer, Celgene, Celltrion, Centocor, Chugai, EBEWE Pharma, Eli Lilly and Company, Medac, MSD (Schering-Plough), Mundipharma, Novartis, Pfizer (Wyeth), Roche, Sanofi-Aventis, and UCB Pharma

FRI0333 ACHIEVEMENT OF VERY LOW DISEASE ACTIVITY AND REMISSION TREATMENT TARGETS IS ASSOCIATED WITH REDUCED RADIOGRAPHIC PROGRESSION IN PATIENTS WITH PSORIATIC ARTHRITIS TREATED WITH CERTOLIZUMAB PEGOL

Background:

Several disease activity measures and thresholds have been recommended as psoriatic arthritis (PsA) treatment targets, although consensus on the most appropriate assessment tool is lacking.1Reports suggest low disease activity (LDA) and remission may be associated with minimal structural progression in PsA.2

Objectives:

To report the relationship between PsA disease activity and structural progression over 216 weeks’ (wks) treatment with certolizumab pegol (CZP), an Fc-free, PEGylated, tumour necrosis factor inhibitor (TNFi) that has shown long-term efficacy and safety in PsA.3

Methods:

Patients (pts) enrolled in RAPID-PsA (NCT01087788) with active PsA (≥3 tender joints; ≥3 swollen joints; ESR ≥28 mm/hour and/or CRP >upper limit of normal) who had failed treatment with ≥1 csDMARD were randomised 1:1:1 to CZP 200 mg every 2 wks (Q2W), CZP 400 mg every 4 wks (Q4W), or placebo (PBO). All CZP pts received CZP 400 mg at Wks 0/2/4. PBO pts were re-randomised to CZP 200 mg Q2W or 400 mg Q4W at Wk 16 or 24.3

Pts were heterogenous for structural damage and disease duration at baseline. Disease activity was assessed using minimal disease activity (MDA) criteria (MDA: 5–6/7 criteria; very LDA [VLDA]: 7/7 criteria), Psoriatic Arthritis Disease Activity Score (PASDAS) (LDA: >1.9–≤3.2; remission: ≤1.9), or Disease Activity Index for Psoriatic Arthritis (DAPSA) (LDA: >4–≤14; remission: ≤4). Radiographs were read in four reading campaigns using the van der Heijde modified Total Sharp Score (mTSS) for PsA. A risk of structural progression (RSP) subgroup (baseline mTSS >median for all pts) was also assessed. Mean change from baseline (CFB) in mTSS and associations with disease activity states were estimated using a hierarchical linear mixed effects model (fixed effects: reading campaign/interactions of concurrent disease activity levels with time; random effects: pt/reading campaign nested within pt) which allowed mean mTSS trajectory, and impact of disease activity levels on this, to differ over time.

Results:

407/409 randomised pts were assessed for mTSS at least once. At Wk 0, mean (standard deviation) DAPSA=44.5 (22.7), PASDAS=6.0 (1.1). 3/409 (0.7%) pts reported MDA. The proportion of pts achieving remission/VLDA states increased to Wk 216, as did estimated mean mTSS. Estimated mean mTSS CFB remained low overall (0.46 at Wk 216; standard error 0.16;Figure). Across disease activity measures, remission/VLDA states were associated with mTSS estimated mean CFB ≤0 in both the overall group and RSP subgroup (Table).

Conclusion:

These data indicate that achievement of remission in PsA is important to prevent further structural damage, particularly in pts with pre-existing structural changes. This supports the rationale for strict disease activity targets.

References:

[1]Coates L. Arthritis Rheumatol 2018;70:345–55;2.Tucker LJ. Curr Rheumatol Rep 2018;20:71;3.van der Heijde D. RMD Open 2018;4:e000582.

Table.

Estimated mTSS (mixed effects model)

mTSS estimated mean CFB (standard error)All patients(N=407)RSP(n=202)PASDASRemission-0.20 (0.25)-0.55 (0.49)LDA0.01 (0.23)-0.07 (0.47)>LDA1.31 (0.22)2.54 (0.43)DAPSARemission-0.34 (0.23)-0.67 (0.46)LDA0.40 (0.22)0.81 (0.44)>LDA1.37 (0.24)2.46 (0.48)MDAVLDA-0.40 (0.28)-0.84 (0.55)MDA0.39 (0.24)0.55 (0.48)>MDA0.89 (0.20)1.73 (0.39)

mTSS estimated mean CFB: ≤0; ≤0.5; >0.5. Data to Wk 216 pooled for all pts randomised.

Acknowledgments:

This study was funded by UCB Pharma. Editorial services were provided by Costello Medical.

Disclosure of Interests:

Laura C Coates: None declared, Joseph F. Merola Consultant of: Merck, AbbVie, Dermavant, Eli Lilly, Novartis, Janssen, UCB Pharma, Celgene, Sanofi, Regeneron, Arena, Sun Pharma, Biogen, Pfizer, EMD Sorono, Avotres and LEO Pharma, Arthur Kavanaugh Grant/research support from: Abbott, Amgen, AstraZeneca, BMS, Celgene Corporation, Centocor-Janssen, Pfizer, Roche, UCB – grant/research support, Philip J Mease Grant/research support from: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – grant/research support, Consultant of: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – consultant, Speakers bureau: Abbott, Amgen, Biogen Idec, BMS, Eli Lilly, Genentech, Janssen, Pfizer, UCB – speakers bureau, Owen Davies Employee of: UCB Pharma, Oscar Irvin-Sellers Employee of: UCB Pharma, Tommi Nurminen Employee of: UCB Pharma, Désirée van der Heijde Consultant of: AbbVie, Amgen, Astellas, AstraZeneca, BMS, Boehringer Ingelheim, Celgene, Cyxone, Daiichi, Eisai, Eli-Lilly, Galapagos, Gilead Sciences, Inc., Glaxo-Smith-Kline, Janssen, Merck, Novartis, Pfizer, Regeneron, Roche, Sanofi, Takeda, UCB Pharma; Director of Imaging Rheumatology BV

A single determination of C-reactive protein does not suffice to declare a patient with a diagnosis of axial spondyloarthritis 'CRP-negative'

BACKGROUND

To be eligible to receive treatment with an anti-tumour necrosis factor (TNF), non-radiographic axial spondyloarthritis (nr-axSpA) patients require either elevated levels of C-reactive protein (CRP) (CRP > upper limit of normal (ULN)) or magnetic resonance imaging assessment showing inflammation of the sacroiliac joints, in addition to meeting criteria for high disease activity. Many axSpA patients are classified as 'CRP-negative', or CRP normal, despite having levels close to the ULN, and are therefore formally ineligible for treatment. The aim of this study was to investigate the likelihood of a CRP test indicating elevated levels in axSpA patients that have previously tested CRP normal.

METHODS

RAPID-axSpA (NCT01087762) enrolled patients who were either magnetic resonance imaging positive or had elevated CRP (> ULN: 7.9 mg/L). CRP data from the double-blind period for placebo-randomised patients until re-randomisation to certolizumab pegol (week 16 for ASAS20 non-responders/week 24 for ASAS20 responders) were analysed. CRP was assessed at screening, baseline, and nine time points to week 24. Linear mixed models were used to investigate time trends, variability, and correlations of CRP data.

RESULTS

Of 106 placebo-randomised patients with baseline CRP assessments, 26 (25%) tested CRP normal at baseline, of whom 13 (50%) had ≥ 1 test indicating elevated CRP to week 16. Of 80/106 (75%) patients with elevated baseline CRP, 25 (31%) had ≥ 1 normal CRP test to week 16. Linear mixed models did not reveal changes in mean CRP across placebo patients from baseline to week 24.

CONCLUSIONS

In axSpA patients with CRP < ULN the CRP test should be repeated after ≥ 4 weeks as there is a substantial chance of finding a positive result for elevated CRP at subsequent testing, thereby allowing the patient access to treatment.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01087762 . Registered on 16 March 2010.

PGA×BSA: A Measure of Psoriasis Severity Tested in Patients with Active Psoriatic Arthritis and Treated with Certolizumab Pegol

OBJECTIVE

The product of physician's global assessment and body surface area (PGA×BSA) to assess psoriasis severity has previously been investigated in patients with psoriasis, with the aim of assessing PGA×BSA as an alternative to the time-consuming Psoriasis Area and Severity Index (PASI). Here, we investigate PGA×BSA as an alternative to PASI in patients with psoriatic arthritis (PsA).

METHODS

Analyses used data from the double-blind, placebo-controlled, RAPID-PsA trial (NCT01087788) that investigated the efficacy of certolizumab pegol (CZP) in patients with PsA. Outcomes assessed whether the PGA×BSA and PASI results were comparable, and whether these outcomes correlated with one another or with the Dermatology Life Quality Index (DLQI).

RESULTS

For CZP-treated patients, both PGA×BSA and PASI demonstrated similar sensitivities to treatment between baseline and Week 24, with mean improvements of 77.4% and 69.0%, respectively. Similar improvements were also seen with placebo (PGA×BSA: 3.2%, PASI: 6.1%). Achievement of 75% response criterion in PGA×BSA and PASI was attained by similar proportions of patients with CZP (PGA×BSA75: 59.0%, PASI75: 61.4%) and placebo (PGA × BSA75: 15.1%, PASI75: 15.1%). Cross tabulations showed high concordance between achievement of response outcomes in PGA×BSA and PASI (79.6-95.2%). Spearman correlations revealed strong correlations between PGA×BSA and PASI at baseline (r = 0.78; n = 225) and percentage improvement to Week 24 (r = 0.85; n = 186). Both outcomes were only moderately correlated with DLQI (r = 0.41-0.50; n = 179-249).

CONCLUSION

PGA×BSA is sensitive to changes in skin manifestations in patients with PsA treated with CZP. Further, PGA×BSA correlates strongly with PASI, and achievement of 75% improvement was similar for PGA×BSA and PASI.

Limited radiographic progression and sustained reductions in MRI inflammation in patients with axial spondyloarthritis: 4-year imaging outcomes from the RAPID-axSpA phase III randomised trial

OBJECTIVES

To report 4-year imaging outcomes in the RAPID-axSpA (NCT01087762) study of patients with ankylosing spondylitis (AS) and non-radiographic axial spondyloarthritis (nr-axSpA), treated with certolizumab pegol (CZP).

METHODS

This phase III, randomised trial was placebo-controlled and double-blind to week 24, dose-blind to week 48 and open-label to week 204. Patients fulfilling the Assessment of Spondyloarthritis International Society (ASAS) axSpA criteria with active disease were stratified (AS/nr-axSpA) according to the modified New York (mNY) criteria at randomisation. Spinal radiographs were assessed using the modified Stoke Ankylosing Spondylitis Spine Score (mSASSS). MRI inflammation used the Spondyloarthritis Research Consortium of Canada (SPARCC) score for sacroiliac joints (SIJ) and the Berlin spinal score (remission defined as SPARCC <2 and Berlin ≤2, respectively).

RESULTS

MRI improvements from baseline (BL) to week 12 were maintained to week 204 (SPARCC BL: AS=8.5, nr-axSpA=7.5; SPARCC week 204: AS=1.3, nr-axSpA=2.4; Berlin BL: AS=7.4, nr-axSpA=4.4; Berlin week 204: AS=2.6, nr-axSpA=1.9). 66.7% of patients with AS and 69.6% of patients with nr-axSpA with BL SPARCC scores ≥2, and 65.4% of patients with AS and 57.3% of patients with nr-axSpA with BL Berlin score >2, achieved remission at week 204. Mean mSASSS change in AS from BL to week 204 was 0.98 (95% CI 0.34, 1.63); 0.67 (95% CI 0.21,1.13) from BL to week 96; and 0.31 (95% CI 0.02,0.60) from week 96 to week 204. Corresponding nr-axSpA changes were 0.06 (95% CI -0.17,0.28), -0.01 (95% CI -0.19,0.17) and 0.07 (95% CI -0.07,0.20). 4.5% of patients with nr-axSpA fulfilled the mNY criteria at week 204, while 4.3% of patients with AS no longer did so.

CONCLUSIONS

In patients with CZP-treated axSpA, rapid decreases in spinal and SIJ MRI inflammation were maintained to week 204. Overall, 4-year spinal progression was low, with less progression during years 2-4 than 0-2. Radiographic SIJ grading changes demonstrated limited progression.

TRIAL REGISTRATION NUMBER

NCT01087762; Post-results.

Observed Incidence of Uveitis Following Certolizumab Pegol Treatment in Patients With Axial Spondyloarthritis

Objective

Axial spondyloarthritis (axial SpA) is characterized by inflammation of the spine and sacroiliac joints and can also affect extraarticular sites, with the most common manifestation being uveitis. Here we report the incidence of uveitis flares in axial SpA patients from the RAPID‐axSpA trial, including ankylosing spondylitis (AS) and nonradiographic (nr) axial SpA.

Methods

The RAPID‐axSpA (NCT01087762) trial is double‐blind and placebo‐controlled to week 24, dose‐blind to week 48, and open‐label to week 204. Patients were randomized to certolizumab pegol (CZP) or placebo. Placebo patients entering the dose‐blind phase were re‐randomized to CZP. Uveitis events were recorded on extraarticular manifestation or adverse event forms. Events were analyzed in patients with/without history of uveitis, and rates reported per 100 patient‐years.

Results

At baseline, 38 of 218 CZP‐randomized patients (17.4%) and 31 of 107 placebo‐randomized patients (29.0%) had past uveitis history. During the 24‐week double‐blind phase, the rate of uveitis flares was lower in CZP (3.0 [95% confidence interval (95% CI) 0.6–8.8] per 100 patient‐years) than in placebo (10.3 [95% CI 2.8–26.3] per 100 patient‐years). All cases observed during the 24‐week double‐blind phase were in patients with a history of uveitis; in these patients, rates were similarly lower for CZP (17.1 [95% CI 3.5–50.1] per 100 patient‐years) than placebo (38.5 [95% CI 10.5–98.5] per 100 patient‐years). Rates of uveitis flares remained low up to week 96 (4.9 [95% CI 3.2–7.4] per 100 patient‐years) and were similar between AS (4.4 [95% CI 2.3–7.7] per 100 patient‐years) and nr‐axial SpA (5.6 [95% CI 2.9–9.8] per 100 patient‐years).

Conclusion

The rate of uveitis flares was lower for axial SpA patients treated with CZP than placebo during the randomized controlled phase. Incidence of uveitis flares remained low to week 96 and was comparable to rates reported for AS patients receiving other anti–tumor necrosis factor antibodies.

Effect of certolizumab pegol over 96 weeks of treatment on inflammation of the spine and sacroiliac joints, as measured by MRI, and the association between clinical and MRI outcomes in patients with axial spondyloarthritis

OBJECTIVE

To report MRI outcomes and explore the relationship between clinical remission and MRI inflammation in patients with axial spondyloarthritis (axSpA) from the RAPID-axSpA trial, including radiographic (r-)axSpA and non-radiographic (nr-)axSpA.

METHODS

RAPID-axSpA (NCT01087762) was double-blind and placebo-controlled to week 24, dose-blind to week 48 and open-label to week 204. Patients were randomised to certolizumab pegol (CZP) or placebo. Placebo patients entering dose-blind were rerandomised to CZP. MRIs performed at baseline, weeks 12, 48 and 96 were scored by 2 reviewers independently: Spondyloarthritis Research Consortium of Canada (SPARCC) for sacroiliac (SI) joints; Berlin modification of the Ankylosing Spondylitis spine MRI scoring system for disease activity (Berlin) for spine. Inflammation thresholds: SPARCC≥2; Berlin>2. Remission thresholds: SPARCC<2 (SI joints); Berlin≤2 (spine); Ankylosing Spondylitis Disease Activity Score (ASDAS) inactive disease (<1.3, clinical).

RESULTS

Across 163 patients in the MRI set (109 CZP; 54 placebo), week 12 mean changes from baseline in MRI scores were greater for CZP versus placebo: SPARCC: -4.8 (SD 8.6) vs -1.6 (7.8; p<0.001); Berlin: -2.9 (4.2) vs 0.2 (4.8; p<0.001). Improvements were maintained to week 96. Week 12 MRI remission was achieved by 52.6% of patients with baseline MRI inflammation in SI joints, 62.0% in the spine and 37.9% of patients with both. MRI remission rates were sustained to week 96, with similar trends in r-axSpA and nr-axSpA. At week 96, 57.5% vs 65.9% of patients achieving versus not achieving clinical remission had MRI remission.

CONCLUSIONS

CZP reduced inflammation in the spine and SI joints in patients with r-axSpA and nr-axSpA, with improvements maintained over 96 weeks. Substantial proportions of patients achieved MRI remission. Concordance between clinical remission and current definitions of absence of MRI inflammation was limited.

TRIAL REGISTRATION NUMBER

NCT01087762; Post-results.

Early Disease Activity or Clinical Response as Predictors of Long-Term Outcomes With Certolizumab Pegol in Axial Spondyloarthritis or Psoriatic Arthritis

Objective

Early identification of patients unlikely to achieve good long‐term disease control with anti–tumor necrosis factor therapy in axial spondyloarthritis (SpA) and psoriatic arthritis (PsA) is important for physicians following treat‐to‐target recommendations. Here we assess associations between disease activity or clinical response during the first 12 weeks of treatment and attainment of treatment targets at week 48 in axial SpA and PsA patients receiving certolizumab pegol.

Methods

The relationship between disease activity or clinical response during the first 12 weeks of treatment and achievement of week‐48 targets (for axial SpA: inactive disease based on Ankylosing Spondylitis Disease Activity Score [ASDAS] using the C‐reactive protein [CRP] level, or Bath Ankylosing Spondylitis Disease Activity Index <2 with normal CRP level; and for PsA: minimal disease activity) was assessed post hoc using RAPID‐axSpA and RAPID‐PsA trial data.

Results

A clear relationship between disease activity from week 2 to 12 and achievement of week‐48 treatment targets was observed in both axial SpA and PsA populations. In axial SpA, week‐48 ASDAS inactive disease was achieved by 0% of patients (0 of 21) with ASDAS very high disease activity at week 12, compared to 68% of patients (34 of 50) with week‐12 ASDAS inactive disease. For PsA, week‐48 minimal disease activity was achieved by 0% of patients (0 of 26) with Disease Activity Score in 28 joints (DAS28) using the CRP level >5.1 at week 12, compared to 73% of patients (57 of 78) with DAS28‐CRP <2.6. Similar results were observed regardless of the disease activity measure used. Clinical response at week 12 also predicted week‐48 outcomes, though to a lesser extent than disease activity.

Conclusion

Using disease activity and the clinical response state during the first 12 weeks of certolizumab pegol treatment, it was possible to identify a subset of axial SpA and PsA patients unlikely to achieve long‐term treatment goals.

Effect of certolizumab pegol over ninety-six weeks in patients with axial spondyloarthritis: results from a phase III randomized trial

Objective

Previous reports of the RAPID-axSpA trial (NCT01087762) described the efficacy and safety of certolizumab pegol (CZP) over 24 weeks in patients with axial spondyloarthritis (SpA), including ankylosing spondylitis (AS) and nonradiographic axial SpA. We report efficacy and safety data up to week 96 of the study.

Methods

The RAPID-axSpA trial is double-blind and placebo-controlled to week 24, dose-blind to week 48, and open-label to week 204. Outcome variables included Assessment of SpondyloArthritis international Society criteria for 20% and 40% improvement in disease activity (ASAS20/40), ASAS partial remission responses (analyzed by nonresponder imputation), AS Disease Activity Score (ASDAS), ASDAS inactive disease, ASDAS major improvement, Bath AS Disease Activity Index (BASDAI), Bath AS Functional Index (BASFI), and Bath AS Metrology Index (BASMI) linear score (analyzed by the last observation carried forward method). Safety data were collected for patients treated with ≥1 dose of CZP.

Results

Of the 325 patients who were randomized, 218 received CZP from week 0. Of these, 93% completed week 24, 88% completed week 48, and 80% completed week 96. Improvements in ASAS responses were maintained to week 96 (for ASAS20, 67.4%, 72.0%, and 62.8% at weeks 24, 48, and 96, respectively), as well as improvements in ASDAS, BASDAI (mean score 3.3, 3.1, and 3.0 at weeks 24, 48, and 96, respectively), BASFI, and BASMI linear score. Comparable improvements were observed with both dosing regimens (200 mg every 2 weeks or 400 mg every 4 weeks) and in patients with AS and those with nonradiographic axial SpA. In the safety set, adverse events occurred in 279 patients (88.6%) and serious adverse events in 41 (13.0%). No deaths or malignancies were reported.

Conclusion

Clinical improvements to week 24 in both CZP dosing regimens were sustained to week 96. Similar sustained improvements were observed in AS and nonradiographic axial SpA subpopulations. The safety profile was consistent with previous reports from RAPID-axSpA, with no new safety signals observed with longer exposure.

Targeted Nalmefene With Simple Medical Management in the Treatment of Heavy Drinkers: A Randomized Double-Blind Placebo-Controlled Multicenter Study

BACKGROUND

Clinical studies with opioid antagonists for treatment of problem drinking have mainly been conducted in specialized alcohol treatment centers, included structured psychosocial treatment, and have focused on maintaining abstinence after a period of abstinence from alcohol.

METHODS

This multisite, randomized double-blind study investigated targeted nalmefene in reducing heavy drinking. Specialized alcohol treatment centers and private general practices enrolled 403 subjects (328 men, 75 women). Subjects were instructed to take nalmefene 10 to 40 mg (n=242) or placebo (n=161) when they believed drinking to be imminent. After 28 weeks, 57 subjects from the nalmefene group continued into a 24-week randomized withdrawal extension. Concomitant psychosocial intervention was minimal and no treatment goals were imposed. Alcohol consumption was recorded using the time-line follow-back method. Biochemical indicators of alcohol use were also measured.

RESULTS

The mean monthly number of heavy drinking days (HDDs) during the 12-week period before inclusion was 15.5 (SD 6.9) in the nalmefene group and 16.2 (SD 6.9) in the placebo group. During treatment, the mean numbers of HDDs were 8.6 to 9.3 in the nalmefene group and 10.6 to 12.0 in the placebo group (p=0.0065). The levels of serum alanine aminotransferase and gamma-glutamyl transferase decreased in the nalmefene group compared with the placebo group (p=0.0088 and 0.0023). During the randomized withdrawal period, subjects randomized to placebo apparently returned to heavier drinking. Subjects receiving nalmefene reported more nausea, insomnia, fatigue, dizziness, and malaise than subjects on placebo.

CONCLUSIONS

Nalmefene appears to be effective and safe in reducing heavy drinking, even when accompanied by minimal psychosocial support.

Multicenter investigation of the opioid antagonist nalmefene in the treatment of pathological gambling

OBJECTIVE

Pathological gambling is a disabling disorder experienced by approximately 1%-2% of adults and for which there are few empirically validated treatments. The authors examined the efficacy and tolerability of the opioid antagonist nalmefene in the treatment of adults with pathological gambling.

METHOD

A 16-week, randomized, dose-ranging, double-blind, placebo-controlled trial was conducted at 15 outpatient treatment centers across the United States between March 2002 and April 2003. Two hundred seven persons with DSM-IV pathological gambling were randomly assigned to receive nalmefene (25 mg/day, 50 mg/day, or 100 mg/day) or placebo. Scores on the primary outcome measure (Yale-Brown Obsessive Compulsive Scale Modified for Pathological Gambling) were analyzed by using a linear mixed-effects model.

RESULTS

Estimated regression coefficients showed that the 25 mg/day and 50 mg/day nalmefene groups had significantly different scores on the Yale-Brown Obsessive Compulsive Scale Modified for Pathological Gambling, compared to the placebo group. A total of 59.2% of the subjects who received 25 mg/day of nalmefene were rated as "much improved" or "very much improved" at the last evaluation, compared to 34.0% of those who received placebo. Adverse experiences included nausea, dizziness, and insomnia.

CONCLUSIONS

Subjects who received nalmefene had a statistically significant reduction in severity of pathological gambling. Low-dose nalmefene (25 mg/day) appeared efficacious and was associated with few adverse events. Higher doses (50 mg/day and 100 mg/day) resulted in intolerable side effects.

Expression of CYP1A1, CYP1B1 and CYP3A, and polycyclic aromatic hydrocarbon-DNA adduct formation in bronchoalveolar macrophages of smokers and non-smokers

Variability in the expression of enzymes metabolizing carcinogens derived from cigarette smoke may contribute to individual susceptibility to pulmonary carcinogenesis. This study was designed to determine the effects of smoking and 3 major cytochrome P450 (CYP) enzymes, i.e., CYP1A1, CYP1B1 and CYP3A, which metabolize polycyclic aromatic hydrocarbons (PAH) on PAH-DNA adduct formation in the bronchoalveolar macrophages (BAM) of 31 smokers and 16 non-smokers. CYP protein levels were determined by immunoblotting and PAH-DNA adduct levels by the nuclease P1 enhanced (32)P-postlabeling method. The expression of specific CYP forms was confirmed by reverse transcriptase-polymerase chain reaction (RT-PCR) from 10 additional samples. CYP3A protein, CYP3A5 by RT-PCR, was detected in the majority of samples from smokers and non-smokers. The levels of CYP3A appeared to be lower in active smokers than in ex-smokers (p = 0.10) or never smokers (p = 0.02). CYP1A1 was not detectable by either immunoblotting or RT-PCR. The expression of CYP1B1 was low or undetectable in most samples. The PAH-DNA adduct levels were higher (mean 1.57/10(8) nucleotides) in samples from smokers compared with non-smokers (mean 0.42/10(8) nucleotides, p < 0.001) and the number of adducts correlated with the number of cigarettes smoked daily (regression analysis, p < 0. 001). Higher levels of adducts were detected in samples from smokers with a high level of CYP3A compared with those with a low level (regression analysis, p = 0.002). As CYP3A5 is abundant in both lung epithelial cells and BAM, its association with adduct formation suggests that this CYP form may be important in the activation of cigarette smoke procarcinogens.

Methodologic issues in epidemiologic risk assessment

This paper reviews methodologic issues pertinent to the application of epidemiology in risk assessment and discusses concerns in the presentation of results from such an activity. Assessment of the health risks associated with occupational and environmental exposures involves four phases: hazard identification, i.e., the detection of the potential for agents to cause adverse health effects in exposed populations; exposure assessment, i.e., the quantification of exposures and the estimation of the characteristics and sizes of the exposed populations; dose-response assessment, i.e., the modeling for risk realization; and risk characterization, i.e., the evaluation of the impact of a change in exposure levels on public health effects. The risk-assessment process involves limitations of exposure data, many assumptions, and subjective choices that need to be considered when using this approach to provide guidance for health policy or action. In view of these uncertainties, we suggest that the provision of estimates of individual risk and disease burden in a population must be accompanied by the corresponding estimates of precision; risks should be presented in a sufficiently disaggregated form so that population heterogeneities are not lost in the data aggregation; and different scenarios and risk models should be applied. The methods are illustrated by an assessment on the health impacts of exposure to silica.

Leukocyte adhesion--an integrated molecular process at the leukocyte plasma membrane

Leukocyte adhesion is of pivotal functional importance, because most leukocyte functions depend on cell-cell contact. It must be strictly controlled, both at the level of specificity and strength of interaction, and therefore several molecular systems are involved. The most important leukocyte adhesion molecules are the selectins, the leukocyte-specific beta2-integrins and the intercellular adhesion molecules. The selectins induce an initial weak contact between cells, whereas firm adhesion is achieved through integrin intercellular adhesion molecular binding. Although studies during the past twenty years have revealed several important features of leukocyte adhesion much is still poorly understood, and further work dealing with several aspects of adhesion is urgently needed. In this short essay, we review some recent developments in the field.

Spontaneous abortions among Finnish flight attendants

We conducted a retrospective cohort study to investigate whether work as a cabin attendant is related to an increased risk for spontaneous abortion. Data on female cabin crew members were linked to medical records on pregnancies. There were 1751 eligible pregnancies for the final analysis. Flight attendants who worked during early pregnancy had a slightly elevated risk of spontaneous abortion, as compared with attendants who were pregnant outside a time span of active flying (odds ratio [OR] = 1.3; 95% confidence interval [CI], 0.9 to 1.8). During the earliest years of the study period (1973 through 1977), the risk seemed to be decreased (OR = 0.4; 95% CI, 0.2 to 1.1), whereas during the later years (1978 through 1994) the risk was increased (OR = 1.6; 95% CI, 1.1 to 2.4). The results are in agreement with earlier studies, showing suggestive evidence of a slightly increased risk of spontaneous abortion among female cabin crew members.

Shift work and reproductive health

Nonstandard workhours may disturb normal body functions, but their relation to reproductive outcome is poorly understood. Two newly published studies suggest an association between rotating shift work and prolonged waiting time to pregnancy. Seven of nine studies on spontaneous abortion suggest that some forms of shift work may be associated with increased risk. Four studies indicate that shift work including night schedules may be related to preterm birth. Moreover, some results have related rotating schedules to intrauterine growth retardation. In the published studies, the type of work schedule examined has varied, and the applied definition of shift work has not necessarily been clear. The main interest areas, however, have been work involving evening and night shifts, rotating or changing schedules, and the irregularity of work patterns. Although the evidence is not ample and remains ambiguous, it is prudent to consider shift work as a potential risk to reproduction.

Pulmonary expression of glutathione S-transferase M3 in lung cancer patients: association with GSTM1 polymorphism, smoking, and asbestos exposure

To characterize the relative roles of glutathione S-transferases (GST) M1 and M3 in the susceptibility to lung cancer, the pulmonary expression of GSTM3 was quantified immunochemically and related to the GSTM1 genotype in 100 lung cancer patients. Among active smokers and recent ex-smokers (for 6 years or less), parenchymal GSTM3 expression was lower in patients with a homozygous GSTM1 null genotype than in those who were GSTM1 positive and had similar smoking habits (P < 0.001 and P = 0.004, respectively). However, in long-term ex-smokers (for 15 years or longer) GSTM3 was not affected by the GSTM1 genotype. Among active smokers and recent ex-smokers who were homozygous GSTM1 null, those with a definite or probable exposure to asbestos expressed GSTM3 at significantly higher levels than those for whom it was unlikely (P = 0.04). A similar effect of the homozygous GSTM1 null genotype on GSTM3 expression was not detected in the bronchial epithelium when GSTM3 was visualized immunohistochemically. Different mechanisms may result in an increased risk of either squamous cell or adenocarcinomas in patients with the homozygous GSTM1 null genotype. Low expression of GSTM3 due to smoking in the parenchymal lung of GSTM1 null individuals can theoretically favor the development of adenocarcinoma. Our data indicated a predominance of this tumor type in patients with low expression of GSTM3.

Maternal pesticide exposure and pregnancy outcome

Exposure to pesticides is inherent in many agricultural jobs. Most of the interest in connection with pesticides and pregnancy outcome has been directed to birth defects. Some indications of an elevated risk of limb anomalies have been associated with ecologic exposure, maternal environmental exposure to pesticides determined by the mother's place of residence, and parental occupation involving potential pesticide exposure. Orofacial clefts have been related to maternal environmental exposure to pesticides and exposure in agricultural work. Moreover, there is evidence that maternal agricultural occupation and pesticide exposure may be associated with elevated risk of spontaneous abortion and stillbirth. However, some studies have found no indication of reproductive hazards but, altogether, the epidemiologic evidence is inconclusive as regards the risk of adverse pregnancy outcome.

Female noise exposure, shift work, and reproduction

In addition to having possible direct effects on the fetus, noise induces a stress reaction in the mother, possibly causing reproductive disturbances. In shift work, many physiological functions and systems that are circadian in nature can be disturbed. Study results indicate that occupational noise at the level of approximately 85 dB LAeq(8 h) or higher and shift work, especially rotating schedules, may have independent negative effects on birth weight and length of gestation. Some forms of shift work have also been associated with early fetal loss. Moreover, some results have related noise exposure and shift work to menstrual disturbance and infertility. Although the evidence is not ample, it is prudent to consider exposure to high-level noise and shift work as risks to reproduction.

Agricultural work during pregnancy and selected structural malformations in Finland

We studied the relation between birth defects and maternal agricultural work in a nationwide time- and area-matched case-referent series of 1,306 pairs of infants (581 orofacial clefts, 365 central nervous system defects, 360 skeletal defects) obtained through the Finnish Register of Congenital Malformations. We supplemented the Register data, including the mothers' latest and previous pregnancies, diseases, consumption of drugs and alcohol, smoking habits, and the like, with detailed interviews on the mothers' work conditions. When all of the birth defects were pooled and agricultural work was compared with nonagricultural work in the first trimester of pregnancy, the adjusted odds ratio was 1.4 [95% confidence interval (CI) = 0.9-2.0]. For orofacial clefts, the corresponding odds ratio was 1.9 (95% CI = 1.1-3.5). An industrial hygienist's blinded assessment indicated that seven mothers of infants with orofacial clefts and three reference mothers had been exposed to pesticides in agricultural work; the adjusted odds ratio for work with pesticide exposure, when compared with unexposed agricultural work, was 1.9 (95% CI = 0.4-8.3). Exposure to solvents did not explain the observed association.

Combined effect of CYP1A1 inducibility and GSTM1 polymorphism on histological type of lung cancer

The combinations of the CYP1A1 inducibility and GSTM1 polymorphism have been investigated in relation to the histological type and peripheral or bronchial location of lung cancer in 54 surgically treated, current smoker lung cancer patients. The induced CYP1A1 was detected in 46 patients (85%) and the homozygous GSTM1 null genotype in 32 patients (59%). The role of CYP1A1 inducibility was found to be more important than that of GSTM1 polymorphism, because the non-inducible CYP1A1 was associated solely with bronchial tumours (P = 0.001), mainly squamous cell carcinomas. In patients with inducible CYP1A1, the expressing GSTM1 gene appeared to have a protective effect against contracting bronchial lung cancer, since 88% (14/16) of the lung tumours in this patient group were peripheral, whereas almost equal numbers of peripheral and bronchial tumours were observed in those patients lacking the gene (P = 0.037).

Shift work, fetal development and course of pregnancy

Information on 1475 mothers of infants with selected structural malformations and an equal number of mothers of "normal" babies was analyzed for a possible relationship between shift work and adverse pregnancy outcome or a complicated course of pregnancy. The primary data were obtained from the Finnish Register of Congenital Malformations supplemented by special interviews on the mothers' work conditions. No signs of a teratogenic risk were observed. The relationship between course of pregnancy and outcomes other than malformations was determined from the noncase mothers' experience. Threatened abortion and pregnancy-induced hypertension were not associated with rotating shift work alone, but in a noisy work environment moderate risks could not be ruled out. Rotating shift work was associated with a slight excess of babies small for their gestational age independently of noise exposure. The results suggest that further studies on the effects of different work schedules on pregnancy are worth consideration.

Physical work load, fetal development and course of pregnancy

The effects of physical work load during pregnancy were analyzed in connection with a nationwide case-referent study that screened for associations between selected structural malformations and occupational exposures. The strain of the occupational activities of 1475 mothers of malformed infants and an equal number of mothers of noncase babies was assessed from a description of the work tasks by an expert using a standardized method reflecting energy expenditure. The noncase mothers' experience revealed a relation between physical load and growth retardation that has also been suggested by other epidemiologic studies. No relation was found between an increase in mean physical load and the occurrence of threatened abortion; yet work involving much standing had an increased risk. Mothers whose work included occasional high physical loads had more pregnancy-induced hypertension. The data showed unexpected associations between physical load and structural malformations.

Occupational noise exposure and course of pregnancy

The study examined the possible relation of occupational noise exposure to adverse pregnancy outcomes. The experience of 1,190 reference mothers from a case-referent study based on the Finnish Register of Congenital Malformations was scrutinized. Exposure to noise was blindly assessed from a description of the mother's workday by two industrial hygienists. Women with an estimated level of noise of around 80 dB LAeq(8 h) or higher were considered exposed. Threatened abortion was not associated with noise exposure alone, but, when it was combined with shift work, the adjusted risk was over twofold. The adjusted risk of pregnancy-induced hypertension was twice as high among the mothers exposed to noise in shift work, and the duration of their pregnancy was shorter. The analyses produced indications of a relation between noise and growth retardation which was not connected with shift work. There were significantly ascending trends in the proportions of these outcomes according to increasing exposure intensity.

Noise exposure during pregnancy and selected structural malformations in infants

The study tested the hypothesis of exposure to noise during pregnancy being teratogenic. It included 1,475 Finnish mothers who had given birth to a malformed child (orofacial cleft or structural defect of the central nervous system, skeleton, or heart and great vessels) and 1,475 reference mothers. A special interview soon after delivery yielded the primary information on exposure. Of the 783 mothers who reported noise exposure in the first trimester, 370 were case mothers and 413 were referents. Hygienic assessment indicated that 102 case mothers and 103 referents had been exposed in the first trimester to a sound level of around 80 dB LAeq(8 h) or higher, the overall odds ratio being 1.0 (95% confidence interval 0.7-1.3). Adjustment for potential confounders by logistic regression methods gave similar results. There was no obvious trend suggesting a hazard when different exposure categories were considered.

Office employment, work with video display terminals, and course of pregnancy. Reference mothers' experience from a Finnish case-referent study of birth defects

In an examination of the possible harmful effects of work in an office environment and the use of a video display terminal (VDT) on the course of pregnancy, the experience of 1,475 reference mothers from a Finnish case-referent study of birth defects was analyzed. The study was based on the national Register of Congenital Malformations, whose data were supplemented with special interviews on mothers' work conditions. The group which worked in an office environment consisted of 239 women, of whom 60 had worked with video display terminals; 805 mothers had not worked in an office. Only mothers who had worked during most of their pregnancy and who had a singleton birth were included; hence 431 women were excluded from the analysis. The information on threatened abortion, length of gestation, birthweight, placental weight, and maternal blood pressure was analyzed. Office work involved no elevated risk of threatened abortion when compared with nonoffice work, and among the VDT users the proportion with symptoms related to an impending early termination of pregnancy was similar to that of other office workers. No unfavorable effects on the length of gestation were observed between the compared groups, and there were no differences in the birthweight of the babies when adjustment was made for gestational age or the other aspects under consideration. Thus the results did not suggest that office employment or work with video display terminals would be harmful for pregnancy.

Birth defects and exposure to video display terminals during pregnancy. A Finnish case-referent study

In a test of the widely publicized allegation that exposure to video display terminals causes birth defects, interview forms of mothers of 1 475 children reported consecutively to the Finnish Register of Congenital Malformations to have defects of the central nervous system, orofacial clefts, skeletal defects, or cardiovascular malformations and the forms of the same number of their paired referents were studied. The scrutiny revealed 490 mothers with occupational titles indicating potential exposure to video display terminals. Of the 490, 235 were case mothers and 255 were referents. Then, unaware of the case-referent status, three members of the research team perused the mothers' interview descriptions of workday activities for information indicating exposure to video display terminals. Work with such terminals during the first trimester of pregnancy was ascertained for 111 mothers. Of these, 51 were case mothers and 60 were referents. The comparison of the mothers exposed to video display terminals during the first trimester with those not exposed at all showed a crude odds-ratio point estimate of 0.9 with 95% confidence limits of 0.6 and 1.2. Adjustment for potential confounders by multivariate logistic regression methods did not materially affect the risk estimates. The results did not indicate a teratogenic risk for operators of video display terminals.

Radiographic versus direct measurements of the spinal canal at lumbar vertebrae L3-L5 and their relations to age and body stature

The role of the narrow lumbar spinal canal in back and sciatic pain is well established. The accuracy of measurements obtained from lumbar radiographs was therefore analyzed in lumbar spine specimens taken from 132 male cadavers. After removal of soft tissues, the same distances were measured on the bones of 80 specimens. Comparisons were made after correction for magnification, the radiographic measurements of interpedicular distances being, on average, 2 mm greater at L3 than the osteologic ones and 4 mm greater at L5. Interarticular distances, midsagittal diameters, and pedicular lengths were, on average, 1 mm greater and foraminal anteroposterior measurements 1 mm less than the osteologic ones. Body stature correlated with interpedicular and interarticular distances, pedicular length, and foraminal anteroposterior measurements. In older age groups, the midsagittal diameter tended to be reduced. A number of correlations were found between the five measurements, e.g. between the anteroposterior diameter of the intervertebral foramen and the pedicular length. Measurements in the transverse plane were independent of those in the anteroposterior plane. These results confirm and amplify preliminary observations and indicate the potential value of simple measurements on lumbar spine films as an alternative to more sophisticated and expensive radiologic investigations.

Low-back pain in nurses and some loading factors of work

Questionnaires were sent to qualified nurses (QNs) and nursing aides (NAs) to study the prevalence of low-back pain (LBP) and sciatica in relation to age, work-load, free time activities, menstruation, pregnancies and number of children. LBP and sciatica severe enough to make them unfit for daily tasks were significantly more common in NAs. Back injury and disability pension due to sciatic symptoms were also more common in NAs. Occupationally, NAs had twice the amount of lifting, bending, and rotation, while QNs reported more sitting and standing at work. Under the age of 30, the heaviness of the work was related to LBP in both NAs and QNs. It was concluded that prevention should be directed to improvements in the occupational work load, particularly for younger nurses.

Screening for occupational exposures and congenital malformations

Since 1976 the Finnish matched-pair Register of Congenital Malformations has been linked to a special project which screens for associations between selected congenital malformations and chemical and physical exposures during early pregnancy. Case mothers and their referents are personally interviewed. Exposure data are quantitated blindly by a team of industrial hygienists and occupational health experts. An analysis of data from 1,047 pairs is now underway. The pairs consist of 289 defects of the central nervous system, 421 orofacial clefts, 200 selected structural malformations of the skeleton, and 137 selected cardiovascular defects. Exposure to organic solvents was associated with defects of the central nervous system in the initial two-year material. However this association was no longer detectable during the following three-year period. More pairs must be gathered before a reasonable judgment regarding the teratogenic potential of solvents becomes possible.