Source comparison
Stability Comparison: DPP-IV Susceptibility
Both sermorelin and tesamorelin contain the His-Ala DPP-IV cleavage site at positions 1-2, but only tesamorelin has been engineered to address this vulnerability. Sermorelin stability: Sermorelin lacks any N-terminal modification. In biological fluids, DPP-IV
This comparison does not assign a generated winner or score.
- Both sermorelin and tesamorelin contain the His-Ala DPP-IV cleavage site at positions 1-2, but only tesamorelin has been engineered to address this vulnerability.
- Sermorelin stability: Sermorelin lacks any N-terminal modification. In biological fluids, DPP-IV cleaves sermorelin at the His-Ala bond, generating GHRH(3-29), which has significantly reduced receptor binding activity. This degradation occurs rapidly. In preclinical in vivo studies, the short effective half-life of sermorelin requires careful experimental design — particularly precise timing of administration relative to measurement endpoints.
- Tesamorelin stability: The trans-3-hexenoic acid group conjugated to tesamorelin's N-terminal tyrosine sterically hinders DPP-IV access to the cleavage site. This extends tesamorelin's functional half-life in biological media compared to sermorelin. The practical result is more sustained GHRH-R engagement with a single administration, which simplifies experimental design and reduces the number of administration events needed to study a given time course.
- Stability summary:
- Amino acid length
- 29
- 44
- N-terminal modification
- None
- Trans-3-hexenoic acid
- DPP-IV susceptibility
- High
- Reduced
- Functional stability in media
- Short
- Extended
- C-terminal group
- Amide
- Molecular weight (approx.)
- ~3,358 Da
- ~5,136 Da