Treatment of ankylosing spondylitis with moxifloxacin.

Abstract: Ankylosing spondylitis (AS) is a human leukocyte antigen (HLA)-B27-associated chronic inflammatory disease of unknown etiology. There are few effective treatments for ankylosing spondylitis, which causes substantial morbidity. The relationship between AS and enterobacteria, especially Klebsiella pneumoniae, has been reported from several groups in several countries. We performed an open-label trial of moxifloxacin, a fluoroquinolone antibiotic, in patients with ankylosing spondylitis. Treatment with moxifloxacin resulted in significant and sustained improvement. At 12 weeks, patients treated with moxifloxacin had significantly greater improvement in primary outcome measures (P < 0.001). The moxifloxacin group also had significantly greater improvement in many of the secondary outcome measures (P < 0.001). In this twelve-week trial, moxifloxacin was safe, well tolerated, and associated with improvement in the inflammatory symptoms of AS.

Key Words: ankylosing spondylitis, moxifloxacin

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Ankylosing spondylitis (AS) is a human leukocyte antigen (HLA)-B27-associated chronic inflammatory disease of unknown etiology. Usually it affects the sacroiliac joints at early stages and may involve the axial skeleton at later stages of the disease. AS belongs to the group of spondyloarthropathies. This group of disorders constitutes a family of related but heterogeneous conditions rather than a single disease with different clinical manifestations. (1)

Although many disease-modifying antirheumatic drugs (DMARDs) and biologic agents are used in the treatment of this disease, new pharmaceutical drugs are required to achieve better efficacy.

Sulfasalazine is effective against this disease. (2-4) Alteration of bowel flora has been a proposed mechanism of action for sulfasalazine, and it has been shown that patients with inflammatory bowel disease treated with sulfasalazine have decreased numbers of nonsporing anaerobes. (5) The relationship between AS and enterobacteria, especially Klebsiella pneumoniae, has been reported from several groups in several countries. (6-8)

Fluoroquinolones are synthetic, broad-spectrum antimicrobial agents in common use for a variety of infections including systemic infections in immune-compromised hosts. (9,10) In addition to their antimicrobial properties, certain quinolones were shown to have immune-modulating activities in animal models and humans. (11) Moxifloxacin (MXF) is a fluoroquinolone with activities against both Gram positive and Gram negative bacteria. It has been suggested that MXF has inhibitory and stimulatory effects on the immune system, primarily by studies that have shown that the production of several cytokines by human and murine leukocytes can be affected by this drug. It has previously been shown (12) that MXF enhances the production of granulocyte-macrophage colony-stimulating factor and interleukin-6 (IL-6) by various organs of cyclophosphamide-injected mice. Other investigators have shown that MXF significantly inhibits IL-8 production by human neutrophils and tumor necrosis factor alpha (TNF-alpha) and IL-1 alpha production by human monocytes stimulated in vitro with lipopolysaccharide (LPS). (13,14)

We performed a study to evaluate the efficacy of moxifloxacin, a fluoroquinolone antibiotic, for the treatment of ankylosing spondylitis.

Methods

Patients

The study was conducted from September to December 2005. Patients were recruited from rheumatology practices in western Turkey. Adult patients (>18 yrs old) fulfilling the modified New York criteria for the diagnosis of AS (15) were recruited for the study. The patients were required to have predominantly the axial form of AS, without active peripheral arthritis, uveitis or inflammatory bowel disease (IBD) at the time of inclusion. The criteria for inclusion were the presence of active disease, as defined by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) [greater than or equal to]30/100 (16) and a serum C-reactive protein (CRP) level [greater than or equal to]10 mg/L.

In addition, disease-modifying antirheumatic drugs had to have been discontinued for at least 1 month before inclusion. Patients who were receiving nonsteroidal antiinflammatory drugs, prednisone ([less than or equal to]10 mg per day), or both were eligible if the doses had been stable for at least four weeks before the study period and continued to be stable during the study period.

A negative pregnancy test result was required for non-menopausal female patients. In female patients of childbearing potential, a urine pregnancy test was done at baseline, and any pregnant women were excluded. Other exclusion criteria included impaired hepatic enzyme tests, impaired renal function, untreated hypertension, diagnosis of other inflammatory joint diseases, impaired bone marrow function, recent serious infections, and any clinically relevant cardiovascular, hepatic, neurologic, endocrine, or other major systemic diseases.

Study Design

This was an open-label, monocenter, 12-week pilot study. This study was approved by the local ethics committee and was carried out in accordance with the ethical principles of the Declaration of Helsinki. Before entering this study, all patients gave written informed consent. Seventy-six eligible patients orally received moxifloxacin (400 mg once daily) for 12 weeks. Clinical and laboratory assessments were performed at the time of screening and on study days 1, 42 and 84. The assessments included a physical examination, evaluation of disease activity, and laboratory tests (complete blood count; measurements of electrolytes, blood urea nitrogen, and creatinine; liver function tests; and urinalysis). Laboratory tests and physical examination were also performed on day 14 to assess the safety of the treatment. Physical examination included measurement of chest expansion (the circumferential difference, in centimeters, between full inspiration and expiration); measurement of lumbar flexion, in centimeters, according to the Schober Index; and measurement, in centimeters, of the distance from the back of the head to the wall while the patient was standing with back and heels against the wall.

Clinical disease variables included duration of morning stiffness (in minutes), degree of spinal pain at night (as represented on a 100-mm visual-analogue scale, with 0 mm indicating the absence of pain and 100 mm the most severe pain), Ankylosing Spondylitis Disease Activity Index, (16) Bath Ankylosing Spondylitis Disease Functional Index (BASFI), (17) physician's and patient's global assessment of disease activity, Schober test (cm), chest expansion (cm), and mean occiput-to-wall measurement (cm). The laboratory evaluation consisted of measurements of the Westergren erythrocyte sedimentation rate and C-reactive protein.

Clinical Evaluation

The primary outcome measures were duration of morning stiffness, degree of nocturnal spinal pain, Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Functional Index, and patient's global assessment of disease activity. Secondary outcome measures included physician's global assessment of disease activity, measures of spinal mobility, erythrocyte sedimentation rate, and C-reactive protein level.

Adverse Events

Patients were monitored for adverse events and abnormal laboratory test results over the course of the study. Vital signs were monitored, and standard hematology, serum chemistry, and urine analysis tests were evaluated.

Statistical Analysis

Significance of the change from baseline was measured by the Wilcoxon signed ranks test. Values of P < 0.05 were considered significant.

Results

The baseline characteristics of the patients are shown in Table 1. Fifty-seven men and 19 women were enrolled. The mean age was 38 years (range, 19-63), and the mean duration of disease was 9 years (range, 1-20). Eighty-eight percent of patients were positive for HLA-B27. The primary reason for withdrawal was inadequate control of AS symptoms. Among the patients receiving moxifloxacin, the proportion of patients who withdrew because of inadequate symptom control was 5% (four patients).

Efficacy

Patients treated with moxifloxacin had significantly greater improvement in primary outcome measures. The moxifloxacin group also had significantly greater improvement in many of the secondary outcome measures (Table 2). There was significant change in the mean of BASDAI (P < 0.001), BASFAI (P < 0.001), physician's global assessment of disease activity (P < 0.001), patient's global assessment of disease activity (P < 0.001), and nocturnal spinal pain (P < 0.001) after 12 weeks. There was significant change in the mean of ESR and CRP after 12 weeks (P < 0.001).

Safety

Moxifloxacin was well tolerated, and no deaths were reported by moxifloxacin-treated patients after 12 weeks of treatment. The most frequently reported adverse events in the 400 mg moxifloxacin treatment group (seen in at least 5% of patients, and excluding worsening of AS) were nausea (6.6%), headache (9.2%), and dizziness (6.6%) (Table 3).

Discussion

The goal of this pilot study was to determine the efficacy and safety of moxifloxacin in patients with active AS. Until recently, AS treatment has mainly been supportive, consisting of NSAIDs and physical therapy. Sulfasalazine, the most frequently studied disease-modifying antirheumatic drug, has been evaluated in eight randomized, placebo-controlled trials. (18) Sulfasalazine is an antimicrobial agent that belongs to the sulfonamide group and has an effective spectrum similar to that of moxifloxacin. However, currently there is significant bacterial resistance to antibiotics from the sulfonamide group. Sulfasalazine appears to be more effective on peripheral arthritis in AS treatment (as is the case with reactive arthritis conditions). Moxifloxacin was our choice from the fluoroquinolone group because with regard to anaerobic bacterial agents, it is superior to the other fluoroquinolones. Antimicrobial agents other than sulfasalazine had not been previously used in AS treatment, even though it bears striking clinical similarities with reactive arthritis conditions, including Reiter syndrome. Fluoroquinolones are used effectively in the treatment of reactive arthritis. The only other disease-modifying antirheumatic drugs that have been evaluated for the treatment of ankylosing spondylitis in randomized, placebo-controlled trials are penicillamine (19) and auranofin, (18) and neither were effective.

Tumor necrosis factor (TNF)-alpha is a proinflammatory cytokine that appears to have a key role in the pathogenesis of AS. (20-22) Biologic treatment agents and specifically TNF-alpha blockers are effective in AS therapy. (23) Klebsiella pneumoniae and oral anaerobic bacteria are powerful stimulators for TNF-alpha and other pro-inflammatory cytokines in humans. (24-26) Moxifloxacin has an immunomodulatory action and significantly inhibits both human and mouse monocytic IL-1 and TNF-alpha synthesis.

In our study, treatment with moxifloxacin resulted in significant improvements in measures of axial diseases, with a sustained response to the drug. The marked reduction in stiffness, pain, and functional limitations with moxifloxacin therapy is particularly promising, since these are the primary problems reported by patients with ankylosing spondylitis and are among the leading causes of disability. The statistically significant improvements in both the patients' and the physicians' global assessments of disease activity demonstrate the benefit of moxifloxacin with respect to overall health.

The only one measure in our study that did not improve significantly with moxifloxacin therapy was the occiput-to-wall measurement. The lack of significant improvement in one of the three measures of spinal mobility, which is not entirely unexpected, may be due to the presence of areas of spinal ossification resulting from prolonged disease.

QT segment prolongation may appear during moxifloxacin treatment. This adverse event has previously been reported in the other fluoroquinolones including moxifloxacin. There is potential to also induce seizure activity. Therefore, patients receiving this therapy should be closely monitored.

The arthritogenic peptide hypotesis postulates that AS results when external antigenic challenge activates autoreactive T-cells that recognize endogenous peptides presented by HLA-B27. In normal situations, the HLA-B27 molecule on the surface of the antigen-presenting cells presents endogenously derived peptides to cell determinant (CD)8+ T-cells. These peptides, which are usually nine amino acids long and have arginine in position 2, are mostly self-derived, but they may also be of bacterial origin. Lysine or arginine is crucial for the interaction with HLA-B27. (27) Porphyromonas gingi-valis has arginine/lysine-specific cysteine proteases. Tannerella forsythensis and Treponema denticola have arginine-specific protease. They are found commensally in the body flora, where they cause sinusitis, pneumonia, intra-abdominal infection, and genitourinary infection in humans, as well as when in conjunction with facultative anaerobic bacteria (ie, Klebsiella pneumoniae, Proteus mirabilis, and Escherichia coli). HLA-B*2704 is strongly associated with ankylosing spondylitis. In contrast, B*2706 is not associated or is weakly associated with AS. (28) HLA-B*2704-specific ligands had Arg (R) on C-terminal domain. (29) The fact that moxifloxacin relieves the axial symptoms of AS and reduces CRP and ESR values demonstrates the validity of the hypothesis that the root cause of this disease may be bacterial. After all, sulfasalazine reduces enterobacteria antibody titrations during treatment for ankylosing spondylitis.

Conclusions

This study suggests that moxifloxacin is effective in patients with AS. We conclude that randomized controlled trials with a longer treatment period are needed to confirm and establish whether moxifloxacin is effective to treat active AS patients.

References

1. Dougados M, van der Linden S, Juhlin R, et al. The European Spondylarthropathy Study Group preliminary criteria for the classification of spondylarthropathy. Arthritis Rheum 1991;34:1218-1227.

2. Feltelius N, Hallgren R. Sulphasalazine in ankylosing spondylitis. Ann Rheum Dis 1986;45:396-399.

3. Davis MJ, Dawes PT, Beswick E, et al. Sulphasalazine therapy in ankylosing spondylitis: its effect on disease activity, immunoglobulin A and the complex immunoglobulin A-alpha-1-antitrypsin. Br J Rheumatol 1989;28:410-413.

4. Ferraz MB, Tugwell P, Goldsmith CH, et al. Meta-analysis of sulfasalazine in ankylosing spondylitis. J Rheumatol 1990;17:1482-1486.

5. Das KM. Sulfasalazine therapy in inflammatory bowel disease. Gastroenterol Clin North Am 1989;18:1-20.

6. Tani Y, Sato H, Tanaka N, et al. Antibodies against bacterial lipopolysaccharides in Japanese patients with ankylosing spondylitis. Br J Rheumatol 1997;36:491-493.

7. Maki-Ikola O, Penttinen M, Von Essen R, et al. IgM, IgG and IgA class enterobacterial antibodies in serum and synovial fluid in patients with ankylosing spondylitis and rheumatoid arthritis. Br J Rheumatol 1997;36:1051-1053.

8. Ahmadi K, Wilson C, Tiwana H, et al. Antibodies to Klebsiella pneumoniae lipopolysaccharide in patients with ankylosing spondylitis. Br J Rheumatol 1998;37:1330-1333.

9. Freifeld A, Marchigiani D, Walsh T, et al. A double-blind comparison of empirical oral and intravenous antibiotic therapy for low-risk febrile patients with neutropenia during cancer chemotherapy. N Engl J Med 1999;341:305-311.

10. Hooper DC, Wolfson JS. Fluoroquinolone antimicrobial agents. N Engl J Med 1991;324:384-394.

11. Dalhoff A, Shalit I. Immunomodulatory effects of quinolones. Lancet Infect Dis 2003;3:359-371.

12. Shalit I, Kletter Y, Halperin D, et al. Immunomodulatory effects of moxifloxacin in comparison to ciprofloxacin and G-CSF in a murine model of cyclophosphamide-induced leukopenia. Eur J Haematol 2001;66:287-296.

13. Weiss T, Shalit I, Blau H, et al. Anti-inflammatory effects of moxifloxacin on activated human monocytic cells: inhibition of NF-kappaB and mitogen-activated protein kinase activation and of synthesis of proinflammatory cytokines. Antimicrob Agents Chemother 2004;48:1974-1982.

14. Araujo FG, Slifer TL, Remington JS. Effect of moxifloxacin on secretion of cytokines by human monocytes stimulated with lipopolysaccharide. Clin Microbiol Infect 2002;8:26-30.

15. van der Linden S, Valkenburg HA, Cats A. Evaluation of diagnostic criteria for ankylosing spondylitis: a proposal for modification of the New York criteria. Arthritis Rheum 1984;27:361-368.

16. Garrett S, Jenkinson T, Kennedy LG, et al. A new approach to defining disease status in ankylosing spondylitis: the Bath Ankylosing Spondylitis Disease Activity Index. J Rheumatol 1994;21:2286-2291.

17. Callin A, Garrett S, Whitelock H, et al. A new approach to defining functional ability in ankylosing spondylitis: the development of the Bath Ankylosing Spondylitis Functional Index. J Rheumatol 1994;21:2281-2285.

18. Toussirot E, Wendling D. Current guidelines for the drug treatment of ankylosing spondylitis. Drugs 1998;56:225-240.

19. Steven MM, Morrison M, Sturrock RD. Penicillamine in ankylosing spondylitis: a double blind placebo controlled trial. J Rheumatol 1985;12:735-737.

20. Gratacos J, Collado A, Filella X, et al. Serum cytokines (IL-6, TNF-alpha, IL-I beta and IFN-gamma) in ankylosing spondylitis: a close correlation between serum IL-6 and disease activity and severity. Br J Rheumatol 1994;33:927-931.

21. Grom AA, Murray KJ, Luyrink L, et al. Patterns of expression of tumor necrosis factor alpha, tumor necrosis factor beta, and their receptors in synovia of patients with juvenile rheumatoid arthritis and juvenile spondylarthropathy. Arthritis Rheum 1996;39:1703-1710.

22. Braun J, Bollow M, Neure L, et al. Use of immunohistologic and in situ hybridization techniques in the examination of sacroiliac joint biopsy specimens from patients with ankylosing spondylitis. Arthritis Rheum 1995;38:499-505.

23. Gorman JD, Sack KE, Davis JC Jr. Treatment of ankylosing spondylitis by inhibition of tumor necrosis factor alpha. N Engl J Med 2002;346:1349-1356.

24. Reato G, Cuffini AM, Tullio V, et al. Immunomodulating effect of antimicrobial agents on cytokine production by human polymorphonuclear neutrophils. Int J Antimicrob Agents 2004;23:150-154.

25. Seymour GJ, Gemmell E. Cytokines in periodontal disease: where to from here? Acta Odontol Scand 2001;59:167-173.

26. Yoshimura A, Hara Y, Kaneko T, et al. Secretion of IL-1 beta, TNF-alpha, IL-8 and IL-lra by human polymorphonuclear leukocytes in response to lipopolysaccharides from periodontopathic bacteria. J Periodontal Res 1997;32:279-286.

27. Huet S, Nixon DF, Rothbard JB, et al. Structural homologies between two HLA B27-restricted peptides suggest residues important for interaction with HLA B27. Int Immunol 1990;2:311-316.

28. Ren EC, Koh WH, Sim D, et al. Possible protective role of HLA-B*2706 for ankylosing spondylitis. Tissue Antigens 1997;49:67-69.

29. Sesma L, Montserrat V, Lamas JR, et al. The peptide repertoires of HLA-B27 subtypes differentially associated to spondyloarthropathy (B*2704 and B*2706) differ by specific changes at three anchor positions. J Biol Chem 2002;277:16744-16749.

Perfection consists not in doing extraordinary things, but in doing
ordinary things extraordinarily well.
--Angelique Arnauld

Mesut Ogrendik, MD

From the Division of Rheumatology, Nazilli State Hospital, Nazilli, Turkey.

Reprint requests to Dr. Mesut Ogrendik, Altintas mah. Kocacami cad., Erten Kocabay Apt., No:2 Kat:6, 09800, Nazilli-Aydin, Turkey. Email: [e-mail]

Accepted September 22, 2006.

RELATED ARTICLE: Key Points

* The relationship between ankylosing spondylitis and enterobacteria, especially Klebsiella pneumoniae, has been reported from several groups in several countries.

* Moxifloxacin is effective in patients with ankylosing spondylitis.

* The cause of ankylosing spondylitis may be bacterial.

* Sulfasalazine reduces enterobacteria antibody titrations during treatment for ankylosing spondylitis.

* Randomized controlled trials with a longer treatment period are needed to confirm and establish whether moxifloxacin is effective to treat active ankylosing spondylitis patients.

Table 1. Baseline characteristics of the patients (a)

Characteristic                       Patients (n = 76)

Male sex (%)                         79
Positive for HLA-B27 (%)             88
Age (yr)                             38 (12)
Duration of disease (yr)              9 (7)
Bath ankylosing spondylitis indices
Activity                             59 (17)
Function                             60 (21)
Pretreatment medications (%)
  NSAIDs                             89
  Corticosteroids                    16
  DMARDs                             42

(a) Values are given as median (SD).
NSAIDs, nonsteroidal anti-inflammatory drugs; DMARDs, disease-modifying
antirheumatic drugs.

Table 2. Outcomes at 12 weeks (a)

                               Baseline     Week 6         Week 12

Primary
Duration of morning stiffness  91.0 (51.6)  45.2 (36.8)**  26.0 (76.4)**
  (min.)
Score for nocturnal spinal     66.2 (17.1)  19.6 (16.4)**  18.9 (13.2)**
  pain (b)
Patient's global assessment    57.0 (19.6)  29.4 (15.7)**  19.3 (12.5)**
  of disease activity (c)
Ankylosing Spondylitis         59.3 (17.2)  31.6 (17.4)**  16.4 (15.1)**
  Disease Activity Index
Ankylosing Spondylitis         60.1 (21.4)  32.3 (18.2)**  17.6 (14.0)**
  Disease Functional Index

Secondary
Physician's global assessment  59.4 (18.2)  32.4 (14.5)**  23.5 (10.6)**
  of disease activity (c)
Spinal mobility
  Schober test (cm)             1.9 (1.7)    2.4 (1.6)*     2.3 (1.2)
  Chest expansion (cm)          1.9 (0.6)    3.4 (1.2)*     3.5 (1.3)
  Mean occiput-to-wall          5.7 (7.2)    4.9 (1.4)      4.8 (7.6)
    measurement (cm)
ESR (mm/h)                     57.3 (18.6)  17.3 (11.2)**  16.2 (9.6)**
CRP (mg/L)                     42.3 (14.5)   8.2 (7.4)**    7.6 (3.8)**

(a) Values are given as median (SD).
(b) Pain was measured on a 100-mm visual-analogue scale, with 0 denoting
none and 100 the most severe pain.
(c) Disease activity was scored on a 100-mm visual-analogue scale.
*P < 0.05; **P < 0.001 (determined by Wilcoxon signed ranks test
compared with baseline).
CRP, C-reactive protein; ESR, erythrocyte sedimentation rate.

Table 3. Adverse events

                                  Moxifloxacin (n = 76)
Adverse event                     No. (%)

Death                             0
Serious adverse events
  Related to study drug           1 (1.3)
Most frequent adverse events (a)
  Gastrointestinal pain           2 (2.6)
  Nausea                          5 (6.6)
  Vomiting                        3 (3.9)
  Diarrhea                        2 (2.6)
  Headache                        7 (9.2)
  Dizziness                       5 (6.6)
  Dry mouth                       2 (2.6)

(a) Ankylosing spondylitis was not included.