Anti-TNF would be the next step up in management. TNF inhibitors would be a good option as they are beneficial for both skin and joints. They would have to be used cautiously due to the patient's past history of TB and unknown therapeutic regime. It is recommended to be screened for active or latent TB according to local protocols prior to commencing treatment and to treat appropriately if required.
Scant evidence that combination therapy with MTX better than monotherapy with biologics alone. However, combination therapy with MTX may help persistence of TNF inhibitors, particularly monoclonal antibodies.
Adding Sulphasalazine could be considered, but the patient has a poor prognosis (high joint count, high CRP), so it is reasonable to escalate to biologic therapy.
IL-17 inhibitors, and IL12/23 inhibitors, are a plausible option although skin not predominant problem and more real life experience with TNF inhibitors.