Diagonal Therapeutics Raises $125M in Series B Funding

Diagonal is preparing its first clinical programme for inherited blood-vessel disorders, where mutations disrupt the signals that keep vessels healthy.

Round size
$125M
Stage
Series B
Headquarters
United States
Announced
Jan 8, 2026

Restoring receptor signalling

Its antibodies bring receptor components together to correct signalling impaired by disease-causing mutations. The lead programme, DIAG723, targets hereditary haemorrhagic telangiectasia and pulmonary arterial hypertension.

Moving from preclinical work

At the financing, DIAG723 had been tested in preclinical disease models. Diagonal planned its first human study in HHT during the first half of 2026.

Where the funding goes

  • Advance clinical development of DIAG723 and additional clustering-antibody candidates.

Sources

  1. Diagonal Therapeutics: funding announcement
  2. Crunchbase News: January 3–9 US funding roundup
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