Single-dose versus low-dose rituximab in corticosteroid-resistant or relapsed ITP: A multicenter, randomized, controlled study

Rituximab alleviates pediatric systemic lupus erythematosus associated refractory immune thrombocytopenia: a case-based review

A complication of pediatric systemic lupus erythematosus (pSLE) is immune thrombocytopenia (ITP). Although corticosteroids and immunoglobulins are frequently used as preliminary treatments, some patients do not respond to them. Rituximab has been reported to be safe and effective in the treatment of pSLE complicated with refractory ITP. Research is currently underway to determine the optimal rituximab dose for these individuals. We report a case of a child with SLE-associated ITP (SLE-ITP) who was successfully treated with rituximab. Rituximab is likely the most viable therapeutic option for refractory SLE-ITP. Furthermore, a comprehensive review of the relevant literature was performed and a concise overview of the pathogenesis and available treatment modalities for pediatric patients diagnosed with SLE and concurrent ITP was provided.

Sovleplenib (HMPL-523), a novel Syk inhibitor, for patients with primary immune thrombocytopenia in China: a randomised, double-blind, placebo-controlled, phase 1b/2 study

BACKGROUND

Spleen tyrosine kinase (Syk) inhibitor is a treatment option for primary immune thrombocytopenia. We aimed to evaluate the safety, tolerability, pharmacokinetics, preliminary activity, and recommended phase 2 dose of sovleplenib in patients with primary immune thrombocytopenia.

METHODS

This randomised, double-blind, placebo-controlled, phase 1b/2 study was conducted at nine hospitals in China. Eligible patients were aged 18-75 years, had an ECOG performance score of 0-1, had primary immune thrombocytopenia for more than 6 months, and did not respond or relapsed after previous first-line treatment or had poor response or postoperative relapse after a splenectomy. Dose-escalation (100 mg, 200 mg, or 300 mg given orally once a day) and dose-expansion phases (recommended phase 2 dose) each consisted of an 8-week, double-blind, placebo-controlled period in which patients were randomly assigned (3:1) to receive sovleplenib or placebo with an interactive web response system followed by a 16-week, open-label period with sovleplenib. Patients, investigators, and the sponsor were masked to treatment allocation during the first 8 weeks. The main efficacy endpoint was the proportion of patients whose platelet count reached 30 × 10⁹ platelets per L or higher and was double of the baseline at two consecutive visits during 0-8 weeks without rescue therapy. Efficacy was evaluated by intention-to-treat. This study is registered with ClinicalTrials.gov, NCT03951623.

FINDINGS

Between May 30, 2019, and April 22, 2021, 62 patients were assessed for eligibility and 45 (73%) were randomly assigned. Patients received at least one dose of the study drug during the 8-week double-blind period (placebo [n=11] and sovleplenib 100 mg [n=6], 200 mg [n=6], 300 mg [n=16], and 400 mg [n=6]; this group was added following the observation of no protocol-specified safety events at the previous doses). All participants were Asian; 18 (40%) of 45 were male and 27 (60%) were female. The median age was 40·0 years (IQR 33·0-50·0). Ten (29%) of 34 patients in sovleplenib groups versus five (45%) of 11 in the placebo group received concomitant anti-primary immune thrombocytopenia therapy. The recommended phase 2 dose was determined as 300 mg once a day. The proportion of patients who met the main efficacy endpoint were three (50%; 95% CI 12-88) in the 100 mg group, three (50%; 12-88) in the 200 mg group, ten (63%; 35-85) in the 300 mg group, and two (33%; 4-78) in the 400 mg group compared with one (9%; 0-41) in the placebo group. The overall response rate in the 300 mg group was 80% (16 of 20 who received continuous sovleplenib plus those who crossed over from placebo) and the durable response rate was 31% (11-59; five of 16) in the continuous sovleplenib 300 mg and 75% (19-99; three of four) crossed from placebo to sovleplenib during 0-24 weeks. During the 28-day safety evaluation period, two grade 2 or worse treatment-related treatment-emergent adverse events occurred in the sovleplenib groups (hypertriglyceridaemia and anaemia). During 0-8 weeks, the most frequent treatment-emergent adverse events were an increase in blood lactate dehydrogenase, haematuria, and urinary tract infection (seven [21%] of 34 in sovleplenib groups vs one [9%] of 11 in the placebo group); and occult blood-positive and hyperuricaemia (four [12%] vs three [27%] for each). No fatal treatment-emergent adverse events were recorded.

INTERPRETATION

Sovleplenib was well tolerated, and the recommended phase 2 dose showed a promising durable response in patients with primary immune thrombocytopenia, which provides evidence for future investigations. A phase 3 trial is ongoing (NCT05029635) to confirm the efficacy and safety of sovleplenib in patients with primary immune thrombocytopenia.

FUNDING

HUTCHMED.

Modeling and affinity maturation of an anti-CD20 nanobody: a comprehensive in-silico investigation

B-cell Non-Hodgkin lymphomas are the malignancies of lymphocytes. CD20 is a membrane protein, which is highly expressed on the cell surface of the B-cells in NHL. Treatments using monoclonal antibodies (mAbs) have resulted in failure in some cases. Nanobodies (NBs), single-domain antibodies with low molecular weights and a high specificity in antigen recognition, could be practical alternatives for traditional mAbs with superior characteristics. To design an optimized NB as a candidate CD20 inhibitor with raised binding affinity to CD20, the structure of anti-CD20 NB was optimized to selectively target CD20. The 3D structure of the NB was constructed based on the optimal templates (6C5W and 5JQH), and the key residues were determined by applying a molecular docking study. After identifying the key residues, some mutations were introduced using a rational protocol to improve the binding affinity of the NB to CD20. The rational mutations were conducted using the experimental design (Taguchi method). Six residues (Ser27, Thr28, Phe29, Ile31, Asp99, and Asn100) were selected as the key residues, and five residues were targeted for rational mutation (Trp, Phe, His, Asp, and Tyr). Based on the mutations suggested by the experimental design, two optimized NB structures were constructed. NB2 showed a remarkable binding affinity to CD20 in docking studies with a binding energy of - 853 kcal/mol. The optimized NB was further evaluated using molecular dynamics simulation. The results revealed that CDR1 (complementarity determining regions1) and CDR3 are essential loops for recognizing the antigen. NB2 could be considered as a potential inhibitor of CD20, though experimental evaluations are needed to confirm it.