FS315 vs Darbepoetin Alfa

Head-to-head comparison of FS315 (Follistatin-315 (FS315)) and Darbepoetin Alfa (Darbepoetin alfa, recombinant human erythropoiesis-stimulating protein) — benefits, dosing, side effects, research data, and where to buy.

Research Score

PropertyFS315Darbepoetin Alfa
CategoryMuscle & PerformanceMuscle & Performance
Full NameFollistatin-315 (FS315)Darbepoetin alfa, recombinant human erythropoiesis-stimulating protein
Molecular Weight~40 kDa≈37,000 Da
Half-LifeN/A; depends on construct/delivery~21 h IV; ~49 h SC
Amino Acids315165
Typical DoseResearch-only; no standardized human dose0.45 mcg/kg weekly SC or 0.75 mcg/kg every 2 weeks
RouteIntramuscular / research expression systemsSubcutaneous/IV
Purity≥98%≥98%
Studies Count95210
Research StatusPre-clinicalClinical

FS315 Benefits

  • activin neutralization
  • muscle growth signaling
  • anti-catabolic support
  • tissue repair modulation

Darbepoetin Alfa Benefits

  • longer-acting erythropoiesis
  • stable hemoglobin
  • increased oxygen delivery
  • may improve aerobic capacity

FS315 Dosing

Research-only recombinant/protein-expression studies|no standardized clinical dose|route varies by platform

Darbepoetin Alfa Dosing

0.45 mcg/kg weekly SC|0.75 mcg/kg every 2 weeks SC|Dose-adjust to hemoglobin response

FS315 Side Effects

  • off-target endocrine effects
  • immune response risk
  • fluid balance changes

Darbepoetin Alfa Side Effects

  • hypertension
  • thromboembolism
  • headache

Research Overview

FS315

Follistatin-315 is a key reference isoform in studies of muscle anabolism and reproductive/endocrine biology. In muscle research, it is relevant because it suppresses activin and can indirectly blunt myostatin pathway output.

Darbepoetin Alfa

Clinical studies show durable hemoglobin correction with less frequent dosing than epoetin alfa. The endurance benefit, where present, would come from improved oxygen-carrying capacity rather than a direct ergogenic pathway.

Ready to buy?

Find both peptides from our verified, lab-tested vendors with purity certificates and third-party testing.

Common Stacking Partners

FS315 stacks with:

CreatineVitamin DLeucine

Darbepoetin Alfa stacks with:

IronFolate
follistatinactivin-inhibitormyostatin-pathwayproteinerythropoiesisvo2-maxendurancelong-acting