Thrombotic thrombocytopenic purpura: 2026 so far

Benefits replicated in cohorts, while early flare and dosing issues emerged.

In the months covered, pooled analyses and real-world studies often linked adding caplacizumab during acute immune TTP to faster platelet recovery and fewer plasma exchange sessions. Several datasets also reported shorter hospital stays. But the results were not all in the same direction. A June single-center review reported short-term exacerbations more often with caplacizumab than with standard care. September reports also noted that platelets can improve before ADAMTS13 activity recovers, and a small case series linked unplanned interruptions during very low ADAMTS13 activity to worsening. Safety reporting depended on the source: postmarketing reports emphasized bleeding (often early) and injection-site/skin reactions, while the June single-center review did not attribute any clinically significant bleeding to caplacizumab. In practice, these reports describe caplacizumab as lowering treatment burden in some settings, while also showing that flare risk and monitoring needs can look different from one report to another.

Research covered in: January 2026, February 2026, June 2026, July 2026, August 2026, September 2026

More routine use reported, with relapse signals varying by cohort.

During the months covered, observational (non-randomized) hospital cohorts repeatedly linked rituximab (an antibody medicine that lowers B cells) use with better outcomes in immune TTP. One cohort reported improved survival, and another reported fewer relapses. German inpatient data showed rituximab use increasing over time. Later single-center data suggested a lower relapse percentage with rituximab, but without statistical clarity in that sample. A registry analysis reported shorter relapse-free survival after rituximab in people of African ancestry, despite similar time to ADAMTS13 recovery. Case reports and consensus documents continued to describe rituximab as an add-on to plasma exchange and steroids, sometimes alongside caplacizumab, and one country-specific consensus noted access/reimbursement constraints. Overall, rituximab was consistently presented as part of combination treatment and relapse-risk planning, but the size and consistency of any relapse-prevention benefit differed across cohorts and subgroups.

Research covered in: January 2026, April 2026, July 2026, August 2026

Evidence progressed from biomarker effects to phase 3 prevention outcomes.

Earlier in the covered months, a summary of two randomized trials including people with congenital or acquired TTP reported that recombinant ADAMTS13 (a lab-made version of the enzyme) increased measured ADAMTS13 activity, but did not show a statistically clear reduction in acute TTP events. By September, a randomized phase 3 open-label crossover trial (a late-stage study where participants switch between treatments, and everyone knows which one they are on) in congenital TTP reported fewer acute and subacute events during recombinant ADAMTS13 prevention than during plasma-based prevention. It also reported higher ADAMTS13 activity and fewer treatment-related side effects. Other reports added background on congenital TTP genetics and on missed recognition in pregnancy/newborn settings, emphasizing ADAMTS13 activity testing and genetic confirmation. For people with congenital TTP, the reports available placed more weight on prevention outcomes for recombinant ADAMTS13, not only lab changes.

Research covered in: April 2026, September 2026

Complication reporting broadened from catheters to procedure hypotension risk.

In the months covered, plasma exchange (a procedure that removes harmful antibodies from the blood) remained a core part of acute immune TTP care, and several reports described the burdens and complications that can come with it. One center reported frequent central-line complications during plasma exchange episodes, including infections and catheter-related clots, and linked major catheter complications with longer hospital stays. A large retrospective review of double-filtration plasmapheresis (a type of plasma exchange) sessions across diseases found low blood pressure in 15.3% of sessions and reported higher risk in immune TTP in adjusted analysis. Several treatment-pattern studies also looked at reducing plasma exchange intensity, such as fewer sessions or earlier stopping, when caplacizumab and immunosuppression were used, but these comparisons were observational. These findings show why acute treatment plans often have to balance fast disease control with the practical risks and logistics of repeated procedures and vascular access.

Research covered in: January 2026, May 2026, June 2026, August 2026, September 2026

Shift toward rapid platforms, repeat testing, and workflow-aware interpretation.

Across the months covered, studies stressed that ADAMTS13 testing is not just a single result. Timing, repeat testing, and how results are combined with other labs can change how clear the diagnosis is. ICU and routine-lab datasets supported repeating ADAMTS13 over time and using stepwise approaches to separate immune TTP from sepsis-related clotting problems. Later work summarized rapid automated platforms that reduced turnaround from days to minutes in published studies, and it described a portable microfluidic assay (a small device that measures blood flow in tiny channels) that still needs broader validation. Several reports also highlighted that TTP-like presentations can have normal or variably low ADAMTS13 depending on the underlying cause, reinforcing the need to sort true TTP from mimics using both context and testing. In these reports, faster and more standardized access to ADAMTS13 activity (and in some studies, antibody or conformation information) was repeatedly framed as a way to confirm or rule out TTP sooner when symptoms do not fit neatly.

Research covered in: February 2026, March 2026, May 2026, July 2026, August 2026, September 2026