Genes for the type-I reaction center and galactolipid synthesis are required for chlorophyll a accumulation in a purple photosynthetic bacterium.

Anoxygenic photosynthesis is diversified into two classes: chlorophototrophy based on a bacterial type-I or type-II reaction center (RC). Whereas the type-I RC contains both bacteriochlorophyll and chlorophyll, type-II RC-based phototrophy relies only on bacteriochlorophyll. However, type-II phototrophic bacteria theoretically have the potential to produce chlorophyll a by the addition of an enzyme, chlorophyll synthase, because the direct precursor for the enzyme, chlorophyllide a, is produced as an intermediate of BChl a biosynthesis. In this study, we attempted to modify the type-II proteobacterial phototroph Rhodovulum sulfidophilum to produce chlorophyll a by introducing chlorophyll synthase, which catalyzes the esterification of a diterpenoid group to chlorophyllide a thereby producing chlorophyll a. However, the resulting strain did not accumulate chlorophyll a, perhaps due to absence of endogenous chlorophyll a-binding proteins. We further heterologously incorporated genes encoding the type-I RC complex to provide a target for chlorophyll a. Heterologous expression of type-I RC subunits, chlorophyll synthase, and galactolipid synthase successfully afforded detectable accumulation of chlorophyll a in Rdv. sulfidophilum. This suggests that the type-I RC can work to accumulate chlorophyll a and that galactolipids are likely necessary for the type-I RC assembly. The evolutionary acquisition of type-I RCs could be related to prior or concomitant acquisition of galactolipids and chlorophylls.

Phase 1/2 study evaluating the safety and efficacy of DSP-7888 dosing emulsion in myelodysplastic syndromes.

DSP-7888 is an immunotherapeutic cancer vaccine derived from the Wilms' tumor gene 1 (WT1) protein. This phase 1/2 open-label study evaluated the safety and efficacy of DSP-7888 dosing emulsion in patients with myelodysplastic syndromes (MDS). DSP-7888 was administered intradermally (3.5 or 10.5 mg) every 2 weeks for 6 months and then every 2-4 weeks until lack of benefit. Twelve patients were treated in phase 1 (3.5 mg, n = 6; 10.5 mg, n = 6), with no dose-limiting toxicities reported. Thus, the 10.5 mg dose was selected as the recommended phase 2 dose, and 35 patients were treated in phase 2. Forty-seven patients received ≥1 dose of the study drug and comprised the safety analysis set. The most common adverse drug reaction (ADR) was injection site reactions (ISR; 91.5%). Grade 3 ISR were common (58.8%) in phase 1 but occurred less frequently in 2 (22.9%) following implementation of risk minimization strategies. Other common ADR were pyrexia (10.6%) and febrile neutropenia (8.5%). In the efficacy analysis set, comprising patients with higher-risk MDS after azacitidine failure in phases 1 and 2 (n = 42), the disease control rate was 19.0%, and the median overall survival (OS) was 8.6 (90% confidence interval [CI], 6.8-10.3) months. Median OS was 10.0 (90% CI, 7.6-11.4) months in patients with a WT1-specific immune response (IR; n = 33) versus 4.1 (90% CI, 2.3-8.1) months in those without a WT1-specific IR (n = 9; P = .0034). The acceptable safety and clinical activity findings observed support the continued development of DSP-7888 dosing emulsion.

Phase I study of alvocidib plus cytarabine/mitoxantrone or cytarabine/daunorubicin for acute myeloid leukemia in Japan.

Therapeutic improvements are needed for patients with acute myeloid leukemia (AML), particularly those who have relapsed or who have treatment-refractory (R/R) AML or newly diagnosed patients with poor prognostic factors. Alvocidib (DSP-2033), a potent cyclin-dependent kinase 9 inhibitor, has previously demonstrated promising clinical activity for the treatment of AML. In this multicenter, open-label, uncontrolled, 3 + 3 phase I study, we investigated the safety and tolerability of alvocidib administered in combination with either cytarabine and mitoxantrone (ACM) for R/R AML or cytarabine/daunorubicin (A + 7 + 3) for newly diagnosed AML. Alvocidib was administered to all patients as a 30-min intravenous (i.v.) bolus (30 mg/m2 /d), followed by a continuous i.v. infusion over 4 h on days 1-3 (60 mg/m2 /d). A total of 10 patients were enrolled: six received ACM (at two dose levels of cytarabine and mitoxantrone) and four received A + 7 + 3. Alvocidib was tolerated and no dose-limiting toxicities were observed. All patients experienced adverse events, of which diarrhea was the most frequent (100%); hematologic events were also common. Alvocidib concentration peaked at the end of dosing (4.5 h after start of administration), plasma accumulation after repeated dosing was minimal and urinary excretion was negligible. The rate of complete remission/complete remission with incomplete hematologic recovery was 66.7% with the ACM regimen in R/R AML, including four complete remission (median duration 13.6 months), and 75% (three complete remission) with the A + 7 + 3 regimen. Further development of alvocidib in hematologic malignancies is warranted. The trial is registered with Clinicaltrials.gov, NCT03563560.

Purification of galectin-1 mutants using an immobilized Galactoseß1-4Fucose affinity adsorbent.

Galectins are a family of lectins characterized by their carbohydrate recognition domains containing eight conserved amino acid residues, which allows the binding of galectin to ß-galactoside sugars such as Galß1-4GlcNAc. Since galectin-glycan interactions occur extracellularly, recombinant galectins are often used for the functional analysis of these interactions. Although it is relatively easy to purify galectins via affinity to Galß1-4GlcNAc using affinity adsorbents such as asialofetuin-Sepharose, it could be difficult to do so with mutated galectins, which may have reduced affinity towards their endogenous ligands. However, this is not the case with Caenorhabditis elegans galectin LEC-6; binding to its endogenous recognition unit Galß1-4Fuc, a unique disaccharide found only in invertebrates, is not necessarily affected by point mutations of the eight well-conserved amino acids. In this study, we constructed mutants of mouse galectin-1 carrying substitutions of each of the eight conserved amino acid residues (H44F, N46D, R48H, V59A, N61D, W68F, E71Q, and R73H) and examined their affinity for Galß1-4GlcNAc and Galß1-4Fuc. These mutants, except W68F, had very low affinity for asialofetuin-Sepharose; however, most of them (with the exception of H44F and R48H) could be purified using Galß1-4Fuc-Sepharose. The affinity of the purified mutant galectins for glycans containing Galß1-4Fuc or Galß1-4GlcNAc moieties was quantitatively examined by frontal affinity chromatography, and the results indicated that the mutants retained the affinity only for Galß1-4Fuc. Given that other mammalian galectins are known to bind Galß1-4Fuc, our data suggest that immobilized Galß1-4Fuc ligands could be generally used for easy one-step affinity purification of mutant galectins.

High-dose thiotepa, in conjunction with melphalan, followed by autologous hematopoietic stem cell transplantation in patients with pediatric solid tumors, including brain tumors.

Among pediatric malignancies, solid tumors, particularly within the central nervous system (CNS), are common. Thiotepa, a myeloablative, high-dose chemotherapeutic (HDT) treatment administered prior to autologous hematopoietic stem cell transplantation (HSCT), can cross the blood-brain barrier and rapidly penetrate the CNS. We evaluated thiotepa HDT in conjunction with melphalan in Japanese patients with pediatric CNS/non-CNS solid tumors in a multicenter, open-label, non-comparative study. Thiotepa (200 mg/m2/day) was administered intravenously (IV) over 24 h on days -12, -11, -5, and -4 before scheduled HSCT. Melphalan (70 mg/m2/day) was administered IV over 1 h on days -11, -5, and -4. The safety analysis population comprised 41 patients, of whom 16 (39.0%) had solid tumors and 25 (61.0%) had brain tumors. The most frequently reported adverse events were diarrhea (40/41 [97.6%] patients) and febrile neutropenia (34/41 [82.9%]). No unexpected safety events were observed, and no events resulted in death or treatment discontinuation. All patients experienced bone marrow suppression and 39/41 (95.1%) achieved engraftment (neutrophil count ≥500/mm3 for 3 consecutive days after HSCT). The survival rate at day 100 post-autologous HSCT was 100%. These data confirm the safety of IV thiotepa plus melphalan HDT prior to autologous HSCT for patients with pediatric CNS/non-CNS solid tumors. Trial registration: JapicCTI-173654.

Efficacy and Safety of Blonanserin Oral Tablet in Adolescents with Schizophrenia: A 6-Week, Randomized Placebo-Controlled Study.

Objectives: To evaluate the short-term efficacy and safety of blonanserin in adolescents with schizophrenia. Methods: This 6-week multicenter, double-blind, randomized, placebo-controlled study investigated fixed-dose blonanserin (8 or 16 mg/day) in patients 12-18 years of age diagnosed with schizophrenia, as indicated by a Positive and Negative Syndrome Scale (PANSS) total score of 60-120 and a Clinical Global Impressions-Severity score of ≥3. The primary endpoint was change from baseline to week 6 in the PANSS total score, using a mixed model for repeated measures analysis. Safety was assessed by the incidence and severity of adverse events (AEs). Results: Among 151 randomized patients, 150 were included in the primary analysis population. Demographic and clinical characteristics were similar across groups at baseline. The rate of study discontinuation was 14.9%, 23.5%, and 28.3% in patients administered with placebo, blonanserin 8 mg/day, and blonanserin 16 mg/day, respectively. The least-squares mean change (95% confidence interval [CI]) from baseline to week 6 in PANSS total score was -10.6 (-16.10 to -5.10), -15.3 (-20.80 to -9.86), and -20.5 (-25.89 to -15.16) in patients administered placebo, 8 mg/day blonanserin, and 16 mg/day blonanserin, respectively. The 16-mg/day blonanserin group showed significantly greater reduction in the PANSS total score than the placebo group (least-squares mean difference [95% CI]: -9.9 [-17.61 to -2.25], p = 0.012, effect size: 0.538), although the 8-mg/day group showed no significant difference. The incidence of AEs such as akathisia, somnolence, and hyperprolactinemia was higher in the blonanserin groups than in the placebo group. AEs associated with blonanserin were generally mild and were consistent with its known profile in adults with schizophrenia. Conclusions: Blonanserin achieved a sufficient efficacy in adolescent patients, and the safety profile was similar to that in adults, which suggests that blonanserin may be a safe treatment option for adolescents with schizophrenia. Study registration number: Japic CTI-111724.

An expanded-access clinical study of thiotepa (DSP-1958) high-dose chemotherapy before autologous hematopoietic stem cell transplantation in patients with malignant lymphoma.

Thiotepa, an antineoplastic ethylenimine alkylating agent that can penetrate the central nervous system, was recently approved in Japan as high-dose chemotherapy prior to autologous hematopoietic stem cell transplantation (HSCT) for patients with malignant lymphoma. To further evaluate the safety and efficacy of thiotepa, a multicenter, open-label, non-comparative, expanded access program was undertaken in Japan, including a larger population of Asian patients with malignant lymphoma. Intravenous thiotepa (200 mg/m2/day) was administered over 2 h on days -4 and -3 before scheduled HSCT, plus intravenous busulfan (0.8 mg/kg) over 2 h every 6 h on days -8, -7, -6 and -5. In the safety analysis population (N = 51), 25 patients (49.0%) had primary central nervous system lymphomas. The most common treatment-emergent adverse event was febrile neutropenia (49/51 [96.1%]). No unexpected safety events were observed, and no event resulted in death or treatment modification. Forty-seven patients (92.2%) had engraftment (neutrophil count ≥ 500/mm3 for three consecutive days after bone-marrow suppression and HSCT). The survival rate at day 100 post-transplantation was 100%. These data confirm the safety of thiotepa prior to autologous HSCT for patients with malignant lymphoma.Trial registration: JapicCTI-173654.

Pharmacokinetics of thiotepa in high-dose regimens for autologous hematopoietic stem cell transplant in Japanese patients with pediatric tumors or adult lymphoma.

PURPOSE: Thiotepa is used in high-dose chemotherapy (HDT) before autologous hematopoietic stem cell transplantation (HSCT) to treat solid tumors and hematological malignancies. This Phase 1 study was conducted to establish the pharmacokinetics (PK) of thiotepa in a Japanese population. METHODS: HDT/HSCT was performed in pediatric patients (≥ 2 years) with solid tumors or brain tumors (thiotepa 200 mg/m2/day IV-infused over 24 h on HSCT Days - 12, - 11, - 5, and - 4 and melphalan 70 mg/m2/day IV-infused over 1 h on Days - 11, - 5, and - 4) and adult patients (≥ 16 years) with malignant lymphoma (thiotepa 200 mg/m2/day 2-h IV-infusion on HSCT Days - 4 and - 3 plus busulfan 0.8 mg/kg 2-h IV-infusion every 6 h from HSCT Days - 8 to - 5). Pharmacokinetics of thiotepa were assessed following initial dose. Safety and efficacy were also evaluated. RESULTS: Nine pediatric and 10 adult patients were enrolled. Mean volume of distribution (Vz) of thiotepa normalized with body surface area (BSA) was lower for pediatric patients (16.4 L/m2) compared with adult patients (26.4 L/m2) as expected due to the higher specific surface area of children. Clearance and biological half-life were similar between pediatric and adult patients. Two serious adverse events (cardiac arrest and pulmonary edema) were observed. Survival rate (Day 100 post-HSCT) was 77.8% (95% CI 36.5-93.9%) for pediatric patients and 100% for adult patients. CONCLUSION: Thiotepa elimination was comparable in pediatric and adult patients with cancer. Lower Vz in pediatric compared with adult patients was expected. HDT with thiotepa prior to autologous HSCT was well tolerated. STUDY REGISTRATION: Japic CTI-163433.

Whole-Genome Sequence of the Purple Photosynthetic Bacterium Rhodovulum sulfidophilum Strain W4.

We report the draft genome sequence of the purple photosynthetic bacterium Rhodovulum sulfidophilum. The photosynthesis gene cluster comprises two segments-a unique feature among photosynthesis gene clusters of purple bacteria. The genome information will be useful for further analysis of bacterial photosynthesis.