ISSCA Peptide Clinical Framework: Labs and Follow-Up

What ISSCA teaches about clinical practice with peptides

The International Society for Stem Cell Application (ISSCA) offers a fully online advanced certification in peptide therapy, with nine modules and 52 lessons, taught by Dr. Greg Jones (NMD) and Dr. Jason Pencek (DC, FNP), both on the ISSCA Scientific Advisory Board; ISSCA issues the certification after an online assessment, and the course has Spanish and Portuguese subtitles¹. The first module, Foundations of Peptide Therapy, presented by Dr. Pencek and Dr. Roni Moya (an immunologist), does more than describe molecules: it proposes a clinical-governance framework for physicians who work with peptides. This article summarizes that framework in our own words and checks it against approved prescribing information and published studies. It contains no doses, schedules or administration instructions.

ISSCA starts with a working definition: peptides are short amino acid chains, roughly 2 to 50 residues, that mimic biological signals by binding specific receptors. That fits the pharmacology literature, which places therapeutic peptides between small molecules and biologics and notes that since insulin in the 1920s more than 60 peptide drugs have been approved in major markets², and more than 80 reached the market according to a later review³. The course page names the problem it is trying to solve: monitoring often starts too late, when baselines and patient-specific risk should be planned before any treatment begins¹.

Patient selection and contraindications in the ISSCA framework

ISSCA splits contraindications into two groups¹. As absolute it lists active cancer or a recent oncologic history, pregnancy and breastfeeding, and allergy to the peptide or its excipients. As relative (use with caution) it lists uncontrolled autoimmune disease, especially with immunomodulatory peptides, advanced renal or hepatic failure, and concomitant immunosuppressants or anticoagulants.

Approved labels confirm the general logic but show that contraindications are molecule-specific. Tesamorelin is contraindicated in active malignancy, pregnancy, hypersensitivity and disruption of the hypothalamic-pituitary axis from hypophysectomy, hypopituitarism, pituitary tumor or surgery, head irradiation or head trauma¹¹. Semaglutide for obesity is contraindicated with a personal or family history of medullary thyroid carcinoma or with multiple endocrine neoplasia type 2, and should be stopped at least two months before a planned pregnancy because of its long half-life⁴. Bremelanotide is contraindicated in uncontrolled hypertension or known cardiovascular disease⁹. None of those three appears on a generic list, so the evaluation has to start from each peptide's label or literature, not only from the shared template.

Baseline labs before starting: the ISSCA panel

Before starting, the ISSCA module calls for a complete history (endocrine, immune, metabolic, cardiovascular and surgical) and a baseline panel¹: complete blood count and a metabolic panel with liver and kidney function; fasting glucose, HbA1c and fasting insulin; lipid panel, apoB, Lp(a), CRP and ESR. Depending on the indication it adds IGF-1, thyroid panel, cortisol, DHEA, testosterone, estradiol, FSH and LH, plus body composition (weight, body fat percentage, skeletal muscle mass and visceral fat).

Several of these tests have direct support in labels. With tesamorelin, glucose status should be evaluated before starting and monitored during treatment, because in phase 3 the share of patients reaching HbA1c ≥ 6.5% was 4.5% versus 1.3% with placebo¹¹. With semaglutide, the label asks for glucose monitoring in type 2 diabetes and warns that hypoglycemia risk rises mainly when combined with insulin or insulin secretagogues⁴. Other items in that panel, such as apoB or Lp(a), are reasonable for cardiometabolic risk stratification but do not come from peptide trials: they are a choice of the framework.

Mechanism-matched monitoring: GLP-1, GH secretagogues and immunomodulators

ISSCA's central idea is to match monitoring to mechanism¹. For metabolic peptides (GLP-1 and GIP agonists) it proposes tracking weight, waist, glucose, HbA1c and lipids. The semaglutide label adds points worth keeping: heart rate at regular intervals, kidney function when vomiting or diarrhea cause volume depletion, gallstone symptoms (cholelithiasis 1.6% versus 0.7% with placebo) and monitoring for depression or suicidal ideation⁴. Gastrointestinal effects dominate the profile: nausea 44% versus 16%, diarrhea 30% versus 16%, vomiting 24% versus 6%⁴. In STEP 1 they were mostly transient and mild to moderate, with 4.5% discontinuing for GI events versus 0.8% on placebo⁷; in SURMOUNT-1 with tirzepatide they clustered during dose escalation, with 4.3–7.1% discontinuing for adverse events versus 2.6%⁸. Details are in tirzepatide side effects.

For GH secretagogues, the module proposes IGF-1, body composition and sleep quality¹. Tesamorelin, the only approved GHRH analog, provides the data-backed model: in the pivotal trial IGF-1 rose 81% versus a 5% fall with placebo¹²; the label calls for close IGF-1 monitoring, reports that 47.4% of patients exceeded 2 SDS and 35.6% exceeded 3 SDS at 26 weeks, and suggests considering discontinuation with persistent elevations¹¹. It also describes fluid retention (edema, arthralgia, carpal tunnel syndrome) that is transient or resolves on stopping¹¹. A review of secretagogues concludes they are generally well tolerated, with concern about rising glucose from reduced insulin sensitivity, and that long, controlled studies, including cancer incidence, are lacking¹³. In short: add glucose and HbA1c to the proposed IGF-1. More in the GH secretagogue guide.

For immunomodulators such as thymosin alpha 1, the framework suggests tracking white cells, CRP and infectious or autoimmune symptoms¹. The biology is plausible: thymosin alpha 1 acts through Toll-like receptors on dendritic cells and drives cytokine production¹⁴. But there is no trial-derived lab schedule for its use outside approved indications; that part is expert judgment. For regenerative peptides (BPC-157, TB-500), it proposes measuring pain, function and, where relevant, musculoskeletal imaging¹; the human evidence for BPC-157 is minimal: a systematic review included 36 studies, 35 preclinical and one clinical, with no clinical safety data¹⁸.

For sexual health peptides, the ISSCA framework anticipates transient blood pressure elevation and flushing with PT-141¹. The bremelanotide label quantifies it: peak rises of 6 mmHg systolic and 3 mmHg diastolic 2 to 4 hours after each administration, with heart rate falling by up to 5 beats per minute and returning to baseline within about 12 hours; nausea in 40% and flushing in 20.3% versus 0.3% with placebo⁹. In the 52-week open-label extension of RECONNECT the most common events were nausea (40.4%), flushing (20.6%) and headache (12.0%), with no new safety signals¹⁰. See the PT-141 and kisspeptin guide.

ISSCA follow-up cadence: 2–4 weeks, 6–12 weeks and maintenance

ISSCA proposes three stages¹. At 2–4 weeks, review adherence and local and systemic tolerance. At 6–12 weeks, compare outcomes with goals, repeat key labs and screen for cumulative effects. Beyond 12 weeks (maintenance), repeat labs every 3 to 6 months and decide whether to continue, pause or change. The triggers to revisit the plan are lack of efficacy, a persistent adverse effect, or biomarkers that do not match the clinical course. With persistent adverse effects the module also asks clinicians to investigate the product's source and possible preparation errors, which ties safety to quality.

Part of that cadence matches the data. Incretin GI effects appear mostly during dose escalation⁸, which supports early contact. In the tesamorelin trials patients were monitored every three months and the IGF-1 rise was already seen at 13 weeks¹¹, which fits the 6–12 week window and quarterly checks. The tesamorelin label also suggests considering discontinuation when there is no clear response by waist circumference or CT¹¹: an approved example of the framework's lack-of-efficacy trigger.

Informed consent and documentation

The ISSCA framework calls for informed consent (blanket or per peptide) that documents risks, benefits and alternatives, charting the product and its concentration, patient education, and systematic recording of outcomes and adverse effects, both for quality of care and legal protection¹. The off-label literature agrees on the principle: physicians should know the evidence, weigh risks and benefits, and prescribe only when they believe it is in the patient's best interest¹⁵. With unapproved peptides, consent should state plainly how much human evidence exists for that specific use.

Product quality: COA, HPLC, mass spectrometry, endotoxin and sterility

The module places sourcing inside safety: it warns that low-quality peptides have variable purity and contamination risk, and recommends verifying purity and potency¹. The chemistry explains why. Solid-phase synthesis can leave peptides with missing or inserted amino acids, racemization, oxidation, protecting-group adducts, counter-ions such as trifluoroacetate, and even contamination with unrelated peptides when good manufacturing practice is lacking¹⁶. A study that bought semaglutide from illegal online pharmacies found vials with 28.6–38.7% more content than labeled, purity of 7.7–14.4% versus the 99% claimed, and endotoxin in every sample, although no viable microorganisms at the time of testing¹⁷.

In practice, a useful certificate of analysis identifies the lot and reports identity by mass spectrometry, purity by HPLC, content, endotoxin and sterility when the product is injectable; the study above used exactly liquid chromatography with mass spectrometry, sterility testing and endotoxin testing¹⁷. How to read each line is covered in peptide certificate of analysis.

Bioavailability: where the framework simplifies

The ISSCA module gives bioavailability ranges by route: 70–90% subcutaneous, 30–60% intranasal, 100% intravenous and 5–15% oral or sublingual for most peptides¹. The literature shows those numbers depend on each molecule and its formulation. Subcutaneous semaglutide has an absolute bioavailability of 89%⁴, but the oral form reaches only 0.4–1% according to the tablet's label⁵, and that is with an absorption enhancer (SNAC) that protects it from degradation in the stomach⁶. Without that kind of technology, most oral peptides are barely absorbed⁶. Those ranges work as a teaching aid, not as values to extrapolate to a specific peptide.