June 2026 Research Update

Across the studies this month, treatment reports focused on how to shorten or support care during acute episodes and what options might exist when the disease comes back. The strongest evidence here comes from retrospective, single-center data suggesting caplacizumab can reduce treatment time in the hospital, while uncertainty remains about why some patients still have early flare-ups during the same episode. [1]

In 165 acute immune-mediated thrombotic thrombocytopenic purpura episodes, episodes treated with caplacizumab used fewer plasma exchange sessions to reach platelet recovery than episodes treated without it. [1]

The same study also reported shorter hospital stays with caplacizumab, while the chance of reaching a lab-defined recovery of the ADAMTS13 enzyme over time was similar between groups. [1]

However, short-term exacerbations (a worsening after initial improvement during the same acute episode) were reported more often in the caplacizumab group than in the standard-care group, even though overall death rates were low and no clinically significant bleeding was attributed to caplacizumab in this cohort. [1]

For patients and caregivers, this adds context to why some treatment plans include caplacizumab during an acute episode: it may reduce how long plasma exchange and hospitalization are needed, at least in some real-world settings. At the same time, this report suggests early flare-ups can still happen and may even be more frequent in some groups, so questions remain about who benefits most and how best to time and monitor treatment; this study was retrospective and from one center. [1]

The papers outside of caplacizumab focused on two practical areas: what happens in individual relapse or suspected cases, and what complications can occur during plasmapheresis procedures. The evidence ranges from case reports (one person) to a large, single-center retrospective review of plasmapheresis sessions, so the level of certainty differs across the findings. [2] [3] [4]

One case report described a patient with relapsed immune thrombotic thrombocytopenic purpura who was treated with daratumumab, which the authors reported as safe and effective in that individual. Because this describes a single person, it cannot show how often this outcome happens in others. [2]

A separate case report described a woman with suspected immune-mediated thrombotic thrombocytopenic purpura who started therapeutic plasma exchange before confirmatory ADAMTS13 testing and then improved in blood counts and hemolysis markers, with ADAMTS13 activity rising later. This report highlights that treatment decisions in real life may start when the blood smear and lab pattern strongly suggest the diagnosis, even before specialized test results return. [3]

In a 15-year retrospective review of 1,022 double-filtration plasmapheresis sessions across many diseases, low blood pressure occurred in 15.3% of sessions and became less common over time. Immune thrombotic thrombocytopenic purpura was linked with a higher risk of low blood pressure during these sessions in the authors' adjusted analysis. [4]

For patients, these reports mainly provide background on the range of care situations clinicians may face: relapse treatments may involve additional immune-targeting medicines in selected cases, and suspected acute episodes may be treated urgently based on characteristic blood and lab patterns while waiting for specialized enzyme testing. The large plasmapheresis review also underscores that side effects like low blood pressure can occur during procedures and that risk may vary by underlying condition and by technical factors, but it did not address long-term outcomes or compare full treatment strategies. [2] [3] [4]

Across these reports, the clearest pattern was that pregnancy-related thrombotic thrombocytopenic purpura (TTP) and similar clotting conditions could show fast improvement in the pregnant person's lab results after plasma exchange, but the pregnancy outcome for the baby was closely tied to gestational age at delivery. The evidence here is limited because it comes from a small retrospective series and one case report, and different pregnancy clotting disorders were grouped together. [5] [6]

In a retrospective series of 10 people treated with therapeutic plasma exchange before 26 weeks for thrombotic microangiopathies (a group of disorders that can include TTP) or certain neurologic conditions, the thrombotic microangiopathy group showed a rapid rise in platelets and ADAMTS13 activity, with drops in markers of red blood cell breakdown and liver stress. Despite maternal lab improvement, five pregnancies ended in fetal or newborn death, and the report noted that all fetal losses occurred before 26 weeks, with better newborn outcomes when delivery occurred after 26 weeks. [5]

That series also described serious complications in some thrombotic microangiopathy cases, including a brain clotting event around delivery in one TTP case, and disseminated intravascular coagulation and pulmonary edema in two HELLP cases (a pregnancy complication that can resemble other clotting disorders). One case thought to be atypical hemolytic uremic syndrome progressed to long-term kidney failure requiring dialysis, even though the baby survived after delivery beyond 26 weeks. [5]

A separate case report described a 28-year-old diagnosed with pregnancy-associated TTP at 34 weeks (ADAMTS13 activity under 10%) who was treated with daily plasma exchange and corticosteroids and then delivered by cesarean section at 36 weeks. Both mother and newborn did well, and no relapse was reported at six weeks after delivery, though the report could not confirm whether the TTP was acquired or inherited because additional testing was not done. [6]

For patients and caregivers, this set of papers mainly adds background on what has been reported in real-world hospital care when TTP (and related pregnancy clotting disorders) occurs during pregnancy. In these limited data, plasma exchange was linked to improvement in the pregnant person's lab markers, but the baby's outcome varied and appeared strongly influenced by how early the pregnancy ended, especially when delivery happened before 26 weeks. Many uncertainties remain because the evidence is small, includes mixed diagnoses, and includes both a case series and a single-person report, so it cannot predict what will happen in any individual pregnancy.

Across this June 2026 evidence, relapse risk in thrombotic thrombocytopenic purpura (TTP) appeared to be more closely linked to certain blood test patterns than to survival differences. In a single-center group, overall survival was high, but some patients relapsed, and specific immune-related and inflammation-related markers helped separate higher- from lower-relapse risk. [7]

In 55 adults with TTP treated with therapeutic plasma exchange, about three-quarters reached a complete response, while about one in four later relapsed. Having an ADAMTS13 inhibitor was strongly linked to a shorter event-free survival (less time before relapse or another event) compared with not having an inhibitor. [7]

Other blood measures at diagnosis also mattered in this study: platelet count, lactate dehydrogenase (a marker often linked with tissue stress), and C-reactive protein (an inflammation marker) were each tied to event-free survival when looked at together. In contrast, overall survival did not differ clearly by inhibitor status in this dataset, which the authors noted may relate to the small number of deaths. [7]

For patients and caregivers, this research mainly adds context for why clinicians often pay close attention to specialized blood testing in TTP, especially tests that detect an ADAMTS13 inhibitor and general markers of inflammation and disease activity. The results suggest these markers may help estimate relapse risk and time until another episode, but they do not prove what will happen for any one person, and the evidence is limited to a relatively small, single-center retrospective study. [7]

Across these papers, the overall message is that long-term brain and heart risks in immune thrombotic thrombocytopenic purpura (iTTP) survivors may be under-recognized when using standard tools developed for the general population. The authors highlight possible silent (no symptoms) brain injuries and the need for better ways to estimate future heart and blood vessel problems in this specific group. Both papers are commentaries rather than new clinical trials, so they summarize concerns and propose next research steps. [8] [9]

For the brain, silent cerebral infarctions (small areas of brain injury often seen only on brain scans) are described as happening at a younger age and more often in iTTP survivors than in the general population. The commentary also lists prior stroke, known cardiovascular disease, and diabetes as risk factors for silent cerebral infarction in iTTP survivors. [9]

For the heart and blood vessels, a letter argues that common cardiovascular risk scores (such as Framingham and ACC/AHA tools) may not accurately predict major adverse cardiovascular events in iTTP survivors. It summarizes several noninvasive ways to look for large-vessel and small-vessel dysfunction, including pulse wave velocity, carotid artery thickness, urine albumin, a heart blood-supply index, retinal imaging, and skin microcirculation imaging, and calls for prospective multicenter studies to see which tests truly predict future events. [8]

For patients and caregivers, this set of papers mainly serves as background: it does not change care on its own, but it explains why some researchers think long-term brain and heart monitoring in iTTP may need approaches tailored to this condition rather than general-population risk calculators. What remains uncertain is how common these silent brain injuries and future cardiovascular events are across different iTTP survivor groups, and which noninvasive tests best identify higher-risk people in a way that improves outcomes. [8] [9]

Across these reports, the main pattern was that conditions that look like thrombotic thrombocytopenic purpura (TTP) at first can have very different underlying causes, including nutritional deficiency, cancer-related vessel injury, inherited ADAMTS13 problems, and autoimmune disease. In these examples, measuring ADAMTS13 activity (and in one case doing genetic testing) helped clarify whether the picture fit TTP or another type of thrombotic microangiopathy (small-blood-vessel injury with low platelets and red blood cell damage). [10] [11] [12] [13]

One report described a 74-year-old woman whose severe vitamin B12 deficiency from pernicious anemia caused a "pseudo-thrombotic microangiopathy" that mimicked TTP, including broken red blood cells on the blood smear. Her ADAMTS13 activity was not severely low (41.3%), and her blood counts recovered after vitamin B12 (cyanocobalamin) replacement, showing how vitamin deficiency can create a misleading TTP-like picture. [10]

Another report described a 62-year-old man with acute kidney failure and thrombotic microangiopathy later linked to metastatic rectal cancer. His ADAMTS13 activity was normal (134.06%), and a kidney biopsy supported secondary thrombotic microangiopathy; plasma exchange improved blood counts but he remained dependent on dialysis, highlighting that kidney outcomes may not follow blood count improvement in some secondary causes. [11]

A third report described a 23-year-old man with congenital (inherited) TTP who had recurrent ischemic strokes; genetic testing found a homozygous ADAMTS13 mutation. This case illustrates that TTP can sometimes be driven by inherited ADAMTS13 changes and may present with major neurologic events, not only low platelets and anemia. [12]

A fourth report described a 33-year-old woman with systemic lupus erythematosus and catastrophic antiphospholipid syndrome who developed multiorgan ischemia along with very low ADAMTS13 activity (5%) but no classic inhibitor detected. After plasma exchange and high-dose steroids, her ADAMTS13 activity rose to 63%, and later testing found non-inhibitory anti-ADAMTS13 antibodies, suggesting a more complex autoimmune link between clotting disorders and ADAMTS13 in some people. [13]

For patients and caregivers, these reports mainly serve as background on why the same TTP-like lab pattern can come from very different causes, including vitamin B12 deficiency, cancer-related small-vessel injury, inherited ADAMTS13 changes, and lupus-related clotting disease. The common thread is that ADAMTS13 activity (and sometimes genetic testing or organ biopsy) can help explain which situation is most likely, but these are single-patient reports, so they cannot show how often each scenario happens or predict outcomes for others.

Across both papers, the main message is that estimates of how common immune-mediated thrombotic thrombocytopenic purpura (iTTP) is can change depending on how cases are identified in large hospital databases. When researchers rely on a general diagnosis code plus a procedure (like plasma exchange), some people with other related blood vessel and clotting conditions may be counted as iTTP, which can inflate incidence and complication rates. [14] [15]

One letter argues that the ICD-10-GM code M31.1 is not specific to iTTP, so using it to define iTTP cases may overestimate how often iTTP occurs. It also notes that kidney injury in iTTP is usually mild and improves quickly, so unusually severe or long-lasting kidney failure in coded datasets could partly reflect misclassification or other illnesses. [14]

A second letter acknowledges the risk of misclassification in administrative data and highlights that excluding people with systemic lupus erythematosus (SLE) can change which patients end up counted. It also notes that including cases from non-specialized centers could make outcomes look worse if diagnosis is delayed or care is less standardized, and that results may reflect the time before caplacizumab was widely used. Even so, the authors state their iTTP cohort broadly matched prior reports for incidence, patient characteristics, and average number of plasma exchange treatments. [15]

For patients and caregivers, this is mainly background context for why different sources may quote different numbers for how common iTTP is, and why reported rates of complications can vary between studies. These papers do not change what iTTP is, but they do underline that database studies can miscount cases when codes are not specific, especially for complications like kidney problems. What remains uncertain is how large the overcount or undercount is in any one dataset without confirming the diagnosis using clinical records and specialized laboratory testing.

Across this month's papers, TTP biology looked less like a single on-off switch and more like a sequence: very low ADAMTS13 enzyme activity sets the stage, but added inflammatory or vessel-wall signals may help drive the full clotting flare-up. One small patient study tracked neutrophil extracellular trap (NET) markers over time, while a lab study suggested ADAMTS13 can also directly influence how platelets respond to collagen, separate from its usual enzyme cutting function. [16] [17]

In 8 people with immune-mediated TTP followed over acute episodes, relapses, and remissions, NET markers were high at the start of acute episodes and then fell with treatment. NET markers did not rise during ADAMTS13 relapses without clear clinical illness, but they increased during overt clinical relapses, supporting the idea that ADAMTS13 deficiency alone may not be enough to trigger strong NET release. [16]

The same study reported that acute episodes treated without caplacizumab showed a second rise in NET markers during the second week that occurred alongside a platelet drop, while episodes treated with caplacizumab did not show this second surge. The authors interpreted this pattern as consistent with a secondary trigger that amplifies inflammation and clotting once von Willebrand factor binds platelets, although this was an observational study and very small. [16]

In lab experiments using washed human and mouse platelets, full-length recombinant ADAMTS13 increased collagen-triggered platelet clumping, activation, and spreading, and this was linked to higher AKT signaling. This effect did not appear to require ADAMTS13 s usual cutting (protease) activity and seemed connected to platelet collagen signaling pathways, but the authors noted that washed-platelet systems may not reflect what happens in the body. [17]

For patients and caregivers, these studies mainly add background about why immune TTP can flare in complex ways: low ADAMTS13 activity may be necessary but not always sufficient for a full episode, and inflammatory pathways (including NET-related signals) may shape when platelet counts fall and organs are affected. The caplacizumab and NET results come from only 8 patients and cannot prove cause and effect, and the ADAMTS13-platelet work was done in the lab, so the real-world importance and exact triggers are still uncertain. [16] [17]

This month included one case report highlighting the extreme end of TTP biology, where widespread small-vessel clotting can rapidly injure the brain and other organs. The report links severe, confirmed ADAMTS13 deficiency with a fast-moving episode that looked like an acute stroke. [18]

The patient, a woman in her mid-40s, arrived with stroke-like symptoms and brain imaging showed multiple infarcts. Testing later confirmed severely reduced ADAMTS13 activity, and she died within 24 hours despite intensive supportive care and plans for plasma exchange. [18]

For patients and caregivers, this report is a reminder of what TTP can do biologically when clotting becomes widespread, especially in the brain, but it describes only one person and does not show how often this happens or which factors predict it. Its main value is as context for why doctors treat suspected severe episodes urgently, rather than as evidence that most people will have outcomes like this. [18]