The panel also issued 32 detailed good practice statements pertaining to initial emergency care and general supportive care, relapse prevention, and the use of TTP treatment strategies that were outside of the panel’s prespecified population, intervention, comparison, and outcome questions.
Among the good practice statements, the panel discussed the need for rapid diagnosis of TTP, which is critical to prevent organ damage and mortality. For example, they stated that the presence of thrombocytopenia and microangiopathic hemolytic anemia without other explanation should prompt a suspicion of TTP in the differential diagnosis. The panel also covered the use of technologies, such as computed tomography and magnetic resonance imaging, to assess brain injury and organ damage. Other good practice statements provide the details of the timing for different treatments.
“Although, rituximab has been used by many clinicians to treat TTP, uncertainty remains about when to add this treatment — should you add it when patient has just arrived in the hospital during the acute setting or should you wait until a patient is recovered,” said Dr Zheng.
In this case, the recommendations and statements suggest to administer rituximab as soon as possible as this approach improves the chance that the patient’s anti-ADAMTS13 autoantibodies will be eliminated by reducing the number of B cells and allowing plasma ADAMTS13 activity to normalize, explained Dr Zheng.
Another important therapy covered by the recommendations and statements is the use of caplacizumab, which prevents thrombus formation and subsequent organ damage and failure by blocking platelet interactions.
“The panel recognized the importance of blocking thrombus formation early when a patient arrives and has started plasma exchange,” said Dr Zheng. “Caplacizumab can be administered right away to block the thrombus formation immediately, instead of waiting a week or 2.”
While the cost of caplacizumab is high, the expense may be offset by the expected benefits. Most importantly, the patient will likely recover faster, and mortality will likely be lower, explained Dr Zheng. Additionally, with faster recovery, the patient can potentially be moved from the intensive care unit and discharged from the hospital faster.
The panel pointed out that there is insufficient evidence for further comparisons of different treatment approaches in iTTP, including between rituximab, corticosteroids, recombinant ADAMTS13, and caplacizumab, and in cTTP, such as recombinant ADAMTS13, meaning future high-quality studies in TTP are needed.
The panel emphasized that the good practice statements are not evidence-based recommendations, as a systematic search or formal review of all available evidence was not conducted.
“These statements are intended to provide a ‘snapshot’ of the care provided to patients with TTP by expert health care providers,” wrote the authors. “[Good practice statements] are intended to guide health care providers who have limited experience in treating TTP. They should be used with caution; the provider’s own clinical judgment, in combination with the individual patient’s clinical situation, values, and preferences, should all be considered.”
Disclosures: Some authors have declared affiliations with or received funding from the pharmaceutical industry. Please refer to the original study for a full list of disclosures.
1. Picod A, Coppo P. Developments in the use of plasma exchange and adjunctive therapies to treat immune-mediated thrombotic thrombocytopenic purpura. Expert Rev Hematol. 2019;12(6):461-471. doi:10.1080/17474086.2019.1619170
2. Zheng XL, Vesely SK, Cataland SR, et al. Good practice statements (GPS) for the clinical care of patients with thrombotic thrombocytopenic purpura. J Thromb Haemost. 2020;18(10):2503-2512. doi:10.1111/jth.15009
This article originally appeared on Hematology Advisor