The indications for ixekizumab have been extended to include the treatment of active psoriatic arthritis in addition to moderate to severe plaque psoriasis.
Ixekizumab is a humanised monoclonal antibody with neutralising activity against the pro-inflammatory cytokine, interleukin-17A. Interleukin-17A is produced by a variety of lymphocytes and has a key role in the defence against bacterial and fungal infections. However, excess production of this cytokine is associated with chronic inflammatory and autoimmune disorders such as psoriasis and psoriatic arthritis.
Ixekizumab targets the same cytokine as secukinumab. In the absence of head-to-head trials, indirect comparisons may be used to compare their efficacy. After 12 weeks of ixekizumab therapy, 87% of patients achieved at least a 75% improvement from baseline psoriasis severity and 38% of patients achieved complete resolution in the UNCOVER-3 trial. For secukinumab, these endpoints were achieved in 81.6% and 28.6% of patients respectively over 12 weeks in the ERASURE trial.
Immunogenicity appears to be higher for the humanised ixekizumab compared to the fully human secukinumab. Up to 17% of patients treated with ixekizumab develop anti-drug antibodies compared to <1% of patients treated with secukinumab. However, only 1% of anti-ixekizumab antibodies were confirmed to be neutralising and associated with a reduced clinical response.
Following an initial dosing regimen tailored to the indication, ixekizumab is usually administered every four weeks as a subcutaneous injection. It may be prescribed as monotherapy or in combination with a conventional disease-modifying antirheumatic drug.
- Gordon KB, Blauvelt A, Papp KA, Langley RG, Luger T, Ohtsuki M, et al. Phase 3 trials of ixekizumab in moderate-to-severe plaque psoriasis. N Engl J Med. 2016; 375: 345-56.
- Langley RG, Elewski BE, Lebwohl M, Reich K, Griffiths CE, Papp K, et al. Secukinumab in plaque psoriasis — results of two phase 3 trials. N Engl J Med. 2014; 371: 326-38.
- Miossec P. Update on interleukin-17: a role in the pathogenesis of inflammatory arthritis and implication for clinical practice. RMD Open. 2017; 3(1): e 00284.
- Taltz® (ixekizumab) Australian approved product information. West Ryde: Eli Lilly Australia. Approved September 2016.