Phase 2, Randomized, Double-Blind, Placebo-Controlled Study of CRD-740, a PDE9 Inhibitor, in Chronic Heart Failure
Bibliographic record
Abstract
BACKGROUND: The beneficial effects of natriuretic peptide receptor activation are mediated by cyclic guanosine monophosphate (cGMP). Phosphodiesterase 9 (PDE9) hydrolyzes cGMP and therefore its inhibition has the potential to increase intracellular cGMP signaling. OBJECTIVES: The aim of this study is to assess the effects of the oral PDE9 inhibitor CRD-740 on plasma and urinary cGMP in patients with heart failure and reduced ejection fraction (HFrEF). METHODS: Patients with HFrEF of >6 months, NYHA functional class II/III, ejection fraction ≤40%, and elevated N-terminal pro-B-type natriuretic peptide were randomized 2:1 to CRD-740 (10 mg twice a day for 2 weeks, then 25 mg twice a day for 10 weeks) or placebo. The primary pharmacodynamic endpoint was the change in plasma cGMP to week 4. RESULTS: Sixty patients were randomized to CRD-740 (n = 40) or placebo (n = 20). Baseline characteristics included ejection fraction 28% ± 7%, with 73% of patients taking sacubitril/valsartan. The placebo-corrected change in plasma cGMP from baseline at week 4 increased with CRD-740, 19.1% ± 26.9% increase vs 8.8% (31.3%) decrease in area under the curve from 0 to 6 hours, respectively, for a least squared mean difference of 26.5% (95% CI: 7.8-45.1; P = 0.003). There was no interaction with the presence/absence of sacubitril/valsartan (P = 0.47). An increase in urinary cGMP was observed with CRD-740 at day 1 (P = 0.012), week 2 (P = 0.014), and week 4 (P = 0.09). No significant between-group differences in systolic blood pressure, hypotension, or serious adverse events were observed. CONCLUSIONS: In this initial phase 2 trial, PDE9 inhibition with CRD-740 was well tolerated and resulted in elevations of plasma and urinary cGMP on top of standard care, including sacubitril/valsartan, supporting the potential of PDE9 inhibition to enhance the beneficial effects of the natriuretic peptide receptor-cGMP pathway incremental to existing heart failure treatments. (Effectiveness of CRD-740 in Heart Failure [CARDINAL-HF]; NCT05409183).
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".