Oral urate-lowering therapy (ULT) is key to treating gout. However, many patients receiving oral ULT do not achieve the target serum urate (SU) levels, partly because some patients cannot tolerate or have contraindications to their use, mainly due to comorbidities. This may lead to uncontrolled gout. In species other than humans and some non-human primates, uricase (urate oxidase) converts urate to allantoin, which is more readily excreted by the kidney. Exogenous uricases, considered “enzyme replacement therapy”, are a therapeutic option for patients with refractory or uncontrolled gout. Current uricases on the market include pegloticase and rasburicase. Uricase treatment rapidly reduces hyperuricemia and tophaceous deposits and improves the quality of life. This review discusses currently approved uricases on the market and some in development; how best to minimize flares, anti-drug antibody (ADA) formation, infusion reactions, and loss of efficacy, and combination with immunomodulation in patients with gout requiring uricase therapy.

Calcium pyrophosphate deposition disease (CPPD), characterized by the presence of calcium pyrophosphate crystals in and around joints, poses diagnostic and therapeutic challenges in rheumatology. This review provides a comprehensive overview of CPPD, focusing on its diagnosis, differential diagnosis, therapeutic challenges, and monitoring, with insights into the association between CPPD and cardiovascular risk. Diagnostics in CPPD rely on identifying CPP crystals in synovial fluid or joint tissues, with imaging modalities such as ultrasound and conventional radiography emerging as valuable tools. The 2023 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) classification criteria prioritize imaging evidence of CPP crystal deposition and recurrent episodes of acute inflammatory arthritis, aiding in standardized diagnosis. Differential diagnosis includes distinguishing CPPD from gout, osteoarthritis, rheumatoid arthritis, basic calcium phosphate deposition disease, and other inflammatory arthropathies. Therapeutic challenges in CPPD management revolve around symptomatic relief, with no targeted therapy to influence CPP deposition currently available. Management strategies include symptom-directed treatments like NSAIDs, steroids and colchicine. IL-6 inhibition with tocilizumab shows promise for refractory cases. Monitoring CPPD involves assessing joint symptoms, inflammation, and cardiovascular risk factors, with regular clinical evaluation. In conclusion, CPPD presents a complex challenge in rheumatology, requiring a nuanced approach to diagnosis and management. Ongoing research is needed to deepen our understanding of CPPD mechanisms and explore novel therapeutic avenues.

The aim of biosimilars is to alleviate the financial burden of biological medicinal products. A most relevant challenge for emerging countries is how to select the best option available. In most cases, price is the major determinant, as budgets are chronically scarce. However, initial savings due to price reductions can be overridden if there is a lack of supply due to product shortages or withdrawals. These events can be prevented by a best-value strategy. According to the concept of best-value medicinal products, price is only one of the various criteria to be considered. The purpose of the present paper is to provide suggestions of criteria that can be useful for selecting the best-value biological in emerging countries. Six criteria, that are not limitative, have been selected as follows: standards of regulatory approval, quality of the product, good distribution practices, security of supply, pharmacovigilance, and price.