STACK CHAPTER

The CIT Blend is the GH Stack (CJC-1295 no-DAC + Ipamorelin) with Tesamorelin added. The GH Stack is already the best-evidenced peptide stack in this book, with Grade B evidence and a decades-long clinical foundation in GHRH+GHRP synergy research. CIT asks the next question: does adding the FDA-approved GHRH analog for visceral fat reduction produce meaningful additional benefit?

The standard GH Stack (pbghstack_v4) operates on the well-established GHRH + GHRP synergy: CJC-1295 (no-DAC) activates the GHRH receptor on pituitary somatotrophs, amplifying GH pulse amplitude; Ipamorelin activates GHS-R1a (ghrelin receptor), triggering GH release and removing somatostatin's suppressive brake. Together they produce a synergistic GH pulse 3-5x larger than either alone. This pulsatile GH protocol drives: GH-mediated lipolysis (fat burning), lean mass support via IGF-1, sleep quality improvement (GHRH enhances SWS), and recovery.

Tesamorelin (EGRIFTA; Food and Drug Administration-approved 2010; 40-amino acid GHRH analog with a trans-3-hexenoic acid modification for stability) is best known for its Phase 3 data in HIV-associated lipodystrophy: -15.2% reduction in trunk/visceral fat at 26 weeks (Falutz 2007, NEJM). Tesamorelin's approval is the only GHRH analog approval for a body composition endpoint. The community's rationale for adding tesamorelin to CJC+Ipa: if Tesamorelin has the strongest visceral fat reduction data of any GHRH analog, stacking it with the already-potent CJC+Ipa foundation might deliver that visceral fat benefit on top of the GH pulse and recovery effects.

THE CENTRAL TENSION

The CIT Blend runs two GHRH analogs simultaneously — CJC-1295 (no-DAC) and Tesamorelin — plus Ipamorelin. The pharmacological question: can two GHRH analogs produce additive GHRH receptor activation, or does the first compound substantially saturate the receptor such that the second adds minimal additional GH release? GHRH receptor dynamics (occupancy, Gq coupling, downstream amplification) determine whether this is additive, synergistic, or redundant. No published study addresses this question for the specific CJC-1295 + Tesamorelin combination. Community clinical practice from the Peptide Partners context suggests value; the mechanistic basis for why two GHRH analogs would produce additive rather than saturating effects is not established. Tesamorelin may contribute through mechanisms beyond pure GHRH receptor activation — including direct adipocyte effects that CJC-1295 alone may not produce at the same magnitude. This remains an open pharmacological question.

Evidence Layer

Grade

Finding

Limitation

GH Stack foundation (CJC + Ipa synergy; Bowers 1991, Teichman 2006, Raun 1998)

B

GHRH+GHRP synergy: 3-5x GH pulse; CJC-1295 IGF-1 +35-120%; Ipamorelin selective GH without cortisol. Established clinical foundation.

CJC+Ipa combination; no CIT-specific trial

Tesamorelin Phase 3 (Falutz 2007; NEJM; n=412; HIV lipodystrophy)

A

Tesamorelin 2mg/day: -15.2% trunk fat at 26 weeks; IGF-1 elevated; FDA approval based on this

HIV lipodystrophy population; not general obesity/body recomp; requires GH-mediated fat oxidation context

Tesamorelin off-label body composition (multiple Phase 2 trials, non-HIV populations)

B (limited)

Visceral fat reduction confirmed in multiple smaller trials beyond HIV population; dose-dependent

Smaller n; specific populations; not direct comparison to CJC alone

CIT triple combination (CJC + Ipa + Tesamorelin)

E (community)

Peptide Partners combination; community reports of enhanced body composition outcomes; clinical practice consensus

No published trial; community consensus only

Two-GHRH-analog pharmacodynamics

No trial

Does running two GHRH analogs simultaneously produce additive GH release or receptor saturation? Unanswered.

No study exists for this specific pharmacological question

Component

Receptor

Half-life

Key Evidence

Unique Contribution to CIT

WADA

CJC-1295 (no-DAC; Mod GRF 1-29)

GHRH receptor (GHRHR)

~30 min

Teichman 2006 (JCEM; Phase 2; IGF-1 +35-120%); GHRH+GHRP synergy literature (Bowers 1991)

Pulsatile GHRH receptor activation; amplitude amplification of GH pulse; sleep enhancement via GHRH

S2 — banned

Ipamorelin

GHS-R1a (ghrelin receptor)

~2 hours

Raun 1998 (Eur J Endocrinol; Phase 1; selective GH without cortisol/prolactin)

GH pulse trigger; somatostatin suppression (removes the GH release brake); selectivity (no cortisol/ACTH)

S2 — banned

Tesamorelin (EGRIFTA)

GHRH receptor (GHRHR)

~26 min; IGF-1 elevation sustained

Falutz 2007 (NEJM Phase 3; -15.2% trunk fat at 26 weeks in HIV lipodystrophy); multiple Phase 2/3 RCTs

Visceral fat reduction evidence (strongest of any GHRH analog); FDA-approved for this endpoint; may have adipocyte-specific effects

S2 — banned

The most pharmacologically important question about the CIT Blend: do CJC-1295 and Tesamorelin produce additive or redundant GHRH receptor activation when run simultaneously?

Standard receptor pharmacology: when a receptor is substantially occupied by agonist A, adding agonist B that targets the same receptor produces diminishing incremental activation if receptor occupancy is approaching saturation. The GHRH receptor is a Class B GPCR with a relatively short stimulatory window before desensitization occurs with sustained activation. If CJC-1295's ~30 min half-life produces substantial GHRH receptor activation during the injection-proximal window, adding Tesamorelin during the same window may not proportionally increase GH release.

Counter-argument for additive benefit: the two analogs have different structures and potentially different receptor occupancy dynamics. Tesamorelin's unique N-terminal modification may produce different receptor binding kinetics than CJC-1295. At the doses used in community protocols (both at relatively low concentrations), receptor saturation may not be reached with either compound alone — leaving room for additive activation when both are present. Additionally, if Tesamorelin has direct adipocyte GHRH receptor effects independent of pituitary GH release, then CIT provides a genuine second mechanism that CJC-1295 alone cannot supply.

The honest answer: no pharmacokinetic or pharmacodynamic study has compared the combination to either compound alone or to the GH Stack. Community clinical experience from Peptide Partners suggests outcomes that justify the triple stack; this is Grade E evidence. The theoretical basis for additive benefit is plausible but not proven.

CJC-1295 WITHOUT DAC ONLY — SAME RULE AS GH STACK

The CIT Blend uses CJC-1295 WITHOUT DAC (also called Mod GRF 1-29) — the pulsatile form with ~30 min half-life. CJC-1295 WITH DAC (8-day half-life; sustained non-pulsatile GH elevation) is incompatible with this protocol for the same reasons documented in the GH Stack chapter: DAC blunts natural GH pulsatility, risks receptor desensitization, and is pharmacologically antithetical to the pulsatile protocol that makes CJC+Ipa synergistic. CJC-1295 DAC also does not pair meaningfully with Tesamorelin (which is pulsatile) in a coherent protocol. Always verify no-DAC.

Component

Dose

Frequency

Notes

CJC-1295 (no-DAC)

100-200 mcg per injection

Daily (before bed primary; optionally AM fasted)

Same as GH Stack; pulsatile; empty stomach mandatory

Ipamorelin

200-300 mcg per injection

Same injection timing as CJC-1295

Same-syringe administration acceptable; empty stomach mandatory

Tesamorelin

1-2 mg per injection

Daily SubQ; same timing as CJC+Ipa or separate injection

FDA-approved dose is 2mg/day; community uses 1-2 mg; some users time separately from CJC+Ipa to reduce receptor competition (though this is theoretical, not evidence-based)

Standard protocol: blended vial (Peptide Partners CIT blend) or separate reconstitution; all three injected SubQ before bed with fasting (2+ hours post-meal, no food 20-30 min after). Empty stomach is mandatory for the CJC+Ipa component for GH pulse fidelity. Tesamorelin can be injected with food in its FDA-approved indication — in the CIT context, most users maintain the same fasted window for all three to simplify the protocol. Cycle: 8-12 weeks; 4-8 weeks off. IGF-1 monitoring: baseline and 6-8 weeks.

ACTIVE MALIGNANCY — CAUTION FOR ALL THREE COMPONENTS

IGF-1 is mitogenic. All three compounds in CIT elevate IGF-1. Active malignancy is a caution for all GH secretagogues and GHRH analogs. Running three GH axis compounds simultaneously may produce larger IGF-1 elevation than any one alone. Physician consultation mandatory for any cancer history. Monitor IGF-1 and do not allow it to exceed the upper limit of the age-appropriate reference range.

Criterion

GH Stack (CJC+Ipa)

CIT Blend (CJC+Ipa+Tesa)

Primary goal

General GH optimization; sleep; recovery; body composition

Body composition with specific visceral fat reduction priority

Evidence base for stack

B (GHRH+GHRP synergy established; Bowers 1991; Teichman 2006; Raun 1998)

B for components (GH Stack B + Tesamorelin A individually); triple combination E

Visceral fat reduction evidence

Indirect (GH-mediated lipolysis)

Direct (Tesamorelin Phase 3: -15.2% trunk fat; NEJM 2007)

Complexity

Moderate (2 compounds)

Higher (3 compounds; two GHRH analogs)

Cost

Lower

Higher (Tesamorelin adds significant cost)

IGF-1 elevation risk

Moderate

Higher (three GH axis compounds)

Glucose monitoring urgency

Standard (annual)

Increased (q4-8 weeks on cycle)

FDA-approved component

No

Yes (Tesamorelin for lipodystrophy)

Falutz J, Allas S, Blot K, et al. (2007). Metabolic effects of a growth hormone-releasing factor in patients with HIV. New England Journal of Medicine. 357(23):2359-2370. [Tesamorelin foundational Phase 3 trial; n=412; -15.2% trunk fat at 26 weeks; FDA approval basis; the primary evidence point that distinguishes CIT from GH Stack.]

Falutz J, et al. (2010). Long-term safety and effects of tesamorelin, a growth hormone-releasing factor analogue, in HIV patients with abdominal fat accumulation. AIDS. 24(14):2269-78. [52-week Tesamorelin data; maintained body composition benefits; long-term safety profile.]

Bowers CY, Sartor AO, Reynolds GA, Badger TM. (1991). On the actions of the growth hormone-releasing hexapeptide, GHRP. Endocrinology. 128(4):2027-35. [GHRH+GHRP synergy; CJC+Ipa foundation evidence.]

Teichman SL, et al. (2006). Prolonged stimulation of GH and IGF-I secretion by CJC-1295. JCEM. 91(3):799-805. [CJC-1295 DAC Phase 2 human data; IGF-1 +35-120%; foundational CJC pharmacology.]

Raun K, et al. (1998). Ipamorelin, the first selective growth hormone secretagogue. Eur J Endocrinol. 139(5):552-61. [Ipamorelin selectivity; GH without cortisol/ACTH; clinical pharmacology foundation.]

CIT is the GH Stack with the FDA-approved visceral fat GHRH analog added. It is well-evidenced in its components and theoretically coherent. The specific triple combination has not been studied, and the two-GHRH-analog pharmacodynamics are the key open question.

• GH Stack alone (CJC+Ipa) is sufficient for: general GH optimization, sleep quality, recovery, body composition, anti-aging GH axis support. Grade B. Simpler, lower cost, lower IGF-1 elevation risk.
• CIT adds value when: visceral fat reduction is a specific priority; the Tesamorelin Phase 3 visceral fat data is the differentiating evidence; patients willing to manage the additional monitoring burden of three GH axis compounds.
• The DAC rule: CJC-1295 without DAC only; same mandatory rule as GH Stack; DAC is incompatible with this pulsatile protocol.
• Empty stomach: mandatory for all three; same fasting rules as GH Stack apply to the whole injection.
• IGF-1 and glucose monitoring: stricter than GH Stack alone; three GH axis compounds; monitor fasting glucose q4-8 weeks on cycle; IGF-1 at baseline and 6-8 weeks.
• stackGrade: B for component-level evidence; the triple combination lacks its own controlled trial.
• WADA: S2 all three components; career-ending for athletes under any testing program.

STACK SUMMARY

CIT Blend: type=stack; slug=cit-stack; stackGrade=B (components individually well-evidenced; triple combination lacks its own trial). COMPONENTS: cjc-1295-no-dac + ipamorelin + tesamorelin. Peptide Partners sells as specific CIT blend. relatedStacks: gh-stack (CJC+Ipa subset). indication: GH axis optimization with specific visceral fat reduction emphasis. WADA S2 ALL THREE — career-ending for athletes under any testing. CJC-1295 (no-DAC): GHRH receptor; ~30 min t½; pulsatile; Teichman 2006 Phase 2; IGF-1 +35-120%; GHRH+GHRP synergy (Bowers 1991). IPAMORELIN: GHS-R1a; selective GH without cortisol/ACTH; Raun 1998; somatostatin suppression. TESAMORELIN (EGRIFTA): GHRH receptor; 40-AA analog + trans-3-hex modification; FDA-approved 2010 (HIV lipodystrophy); Falutz 2007 NEJM (Phase 3; n=412; -15.2% trunk fat 26 weeks; -% IGF-1 ↑); strongest visceral fat GHRH data. THE KEY QUESTION: running two GHRH analogs (CJC + Tesa) simultaneously — additive GH release or GHRH receptor saturation? No published study answers this. Tesamorelin may have direct adipocyte GHRH receptor effects beyond pituitary GH release. PROTOCOL: CJC-1295 no-DAC 100-200 mcg + Ipamorelin 200-300 mcg + Tesamorelin 1-2 mg; all SubQ before bed; fasted 2+ hours; same empty stomach rule as GH Stack; 8-12 week cycles. SAFETY: active malignancy caution (3 GH axis compounds = higher IGF-1 elevation). Glucose monitoring q4-8 weeks on cycle (Tesamorelin FDA prescribing note). IGF-1 at baseline and week 6-8; do not exceed upper reference range. CJC DAC RULE: no-DAC ONLY — same mandatory rule as GH Stack. vs GH STACK: CIT adds Tesamorelin's visceral fat Phase 3 evidence; GH Stack is simpler and lower-monitoring for general GH optimization. CHOOSE CIT when visceral fat reduction is a specific priority. CHOOSE GH STACK when visceral fat is not the primary driver.

— End of CIT Blend —

THE PEPTIDE BIBLE | CIT Blend | For Research & Educational Purposes Only