AX-2025-019142 · Tesamorelin · GSP lot GSP-2501-G3708

Section 1

Results

Measured against the index acceptance specification for the growth-hormone axis peptides class. A specification is a decision the index made; a result is a measurement. See where each threshold came from.

Parameter	Method	Result	Unit	Index spec
Purity	RP-HPLC, 25 min gradient, 214 nm	98.31	% area	≥ 97.0	PASS
Total impurities	RP-HPLC, sum of reported peaks	1.69	% area	≤ 3.0	PASS
Largest single impurity	RP-HPLC — Met sulfoxide (+16 Da)	0.62	% area	≤ 1.00	PASS
Identity — theoretical monoisotopic mass	calculated from molecular formula	5131.9276	Da	—	NOT TESTED
Identity — observed monoisotopic mass	LC-MS, unit resolution (single quadrupole)	5131.9297	Da	—	NOT TESTED
Mass accuracy	observed vs theoretical	+0.4	ppm	± 15	PASS
Total peptide content	by difference from the gravimetric mass balance	90.71	%w/w	—	NOT TESTED
Target-compound content	total peptide content × purity	89.18	%w/w	—	NOT TESTED
Gross fill (as weighed)	five-place balance, under nitrogen	5.38	mg	5 mg declared	NOT TESTED
Recovered target peptide	gross fill × target content	4.798	mg	5 mg claim	NOT TESTED
Recovery against label claim	recovered ÷ claim	96.0	%	90.0 – 110.0	PASS
Water content	Karl Fischer, coulometric, duplicate	4.53	%	≤ 9.0	PASS
Counter-ion (acetate)	anion-exchange ion chromatography	4.16	%	≤ 12.0	PASS
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.60	%	—	NOT TESTED
Endotoxin	not ordered on this submission	not determined	—	≤ 5.0	NOT TESTED
Sterility	not ordered on this submission	not determined	—	no growth	NOT TESTED
Appearance	visual, diffuse light, black and white background	Off-white lyophilised cake, intact	—	white to off-white intact cake	PASS
Reconstitution clarity	reconstituted per submitter procedure	Faint haze, clearing on standing	—	clear, no visible particulates	FAIL
pH (reconstituted, 1 mg/mL)	potentiometric, two-point calibration	5.08	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 25 min gradient	13.10	min	13.07 ± 0.40 (normalised)	PASS
Peak asymmetry (10 % height)	Ph. Eur. 2.2.46	1.32	—	0.80 – 1.50	PASS
Plate count, main peak	N = 5.54 (t/w½)²	29,357	—	≥ 20,000	PASS
Resolution to nearest impurity	vs deamidated (+1 Da)	0.74	—	no index criterion	REPORTED

Section 2

Chromatogram and peak integration

The figure is drawn from the table. It is not an independent illustration — if a number in the table changed, the trace would change with it.

Figure 1. RP-HPLC trace, 25 min gradient, 214 nm. Drawn from the peak-integration table below: peak positions are the reported retention times, peak areas are the reported area percentages, peak widths follow the reported plate count of 29,357, and skew follows the reported asymmetry factor of 1.32. Baseline noise is seeded from the report ID and is illustrative. The lower panel is the same trace at a stated vertical expansion with the slow gradient drift subtracted, because at full scale a 0.62 % impurity against a 98.31 % main peak is a line two pixels tall; the main peak runs off-scale there by design.

#	Peak	RT	Area (µV·s)	% area	Δ mass (Da)
1	Tesamorelin — main peak	13.10	4,778,171	98.31	—
2	Met sulfoxide (+16 Da)	12.57	30,134	0.62	+15.995
3	des-hexenoyl GRF (1-44) (−96 Da)	11.92	29,162	0.60	-96.058
4	deamidated (+1 Da)	12.87	12,637	0.26	+0.984
5	truncated (1-40)	11.53	10,207	0.21	-488.259
Closure check — purity + Σ impurities				100.00	CLOSES

Reporting threshold 0.05 % area. Peaks below it are not reported and are therefore excluded from the total, which overstates purity by their sum — see peak integration.

Section 3

Mass spectrum and identity

Theoretical monoisotopic mass 5131.9276 Da, computed from C221H366N72O67S. All ppm figures on this site are against monoisotopic values — see why that matters.

Figure 2. ESI charge-state envelope, unit-resolution instrument. Sticks are placed at m/z = (M + z × 1.007276)/z for the observed neutral mass of 5131.9297 Da. Sodium (+21.982/z) and potassium (+37.956/z) adducts are shown where the parent charge state exceeds 25 % relative abundance; they are adducts of the same molecule and are not impurities.

Charge	Theoretical m/z	Observed m/z	Δ m/z	Rel. abundance (%)
7+	734.1398	734.1401	0.0003	8.3
6+	856.3285	856.3289	0.0004	53.0
5+	1027.3928	1027.3932	0.0004	100.0
4+	1283.9892	1283.9897	0.0005	57.6
3+	1711.6498	1711.6505	0.0007	8.9

Section 4

Gravimetric mass balance

Water, counter-ion, residual and total peptide content are exhaustive and mutually exclusive categories. They must account for 100 % of the cake mass. The index closes this to within 0.02 pp and the build asserts it.

Component	Determination	%w/w of cake
Water	Karl Fischer	4.53
Counter-ion (acetate)	ion chromatography	4.16
Residual solvent + inorganic residue	estimated	0.60
Total peptide content	by difference	90.71
Total		100.00 CLOSES

Supplier certificate, as declared

The supplier's own figures for this lot, beside the independent measurement. Divergence is assessed against the batch median, not against this single report — see rule AX-R05.

Figure	Supplier COA	This report	Index note
Purity (% area)	98.51	98.31	divergence +0.22 pp vs batch median
Total impurities (% area)	1.49	1.69
Largest single impurity (% area)	0.93	0.62
Water (%)	not stated	4.53
Counter-ion (%)	7.5	4.16
Peptide content (%w/w)	88.4	90.71
Endotoxin (EU/mg)	not stated	not determined
Method stated on certificate	NO	—	no method section — the result cannot be reconciled against any other

Section 5

Provenance and caveats

Where a sample came from changes the weight of the evidence. The index treats it as a first-class field.

Sample provenance: Buyer-sourced
Evidentiary weight: Strongest available evidence in this index.
Chain of custody: Retail purchase → third-party forwarder (17 d) → laboratory (courier, cold pack, 3 d) → assay.
Assay date: 02 Mar 2025
Submitted to the index: 18 Mar 2025
Laboratory: Medutest, Ljubljana, Slovenia
Method basis: 25 min gradient · unit-resolution MS
Verification status: IDENTITY CONSISTENT

What this report does not establish

That the compound is not a near-isobaric alternative. Identity was confirmed at unit mass resolution, which cannot exclude species differing by 1 or 2 Da. The specific alternatives not excluded are named in the identity block above.
That the material is free of bacterial endotoxin. Endotoxin was not measured. No chromatographic result bears on it.
That the material is sterile. Sterility was not tested.
That any other vial in the same lot has the same composition. One vial was tested. Within-lot vial-to-vial variation in this index has a median of 0.28 pp and a 90th percentile of 0.74 pp.
That any other lot from the same supplier has the same composition. Batch-to-batch variation is larger than within-batch variation for every supplier here.
That the material is suitable for administration to a human or an animal. These are research compounds. No result on this site is a safety assessment and the index takes no position on use.
That the material was manufactured by the supplier that sold it. Contract synthesis is normal in this market and twenty-nine batches in the index fingerprint to a bulk from a different company than the one named on the label.

Section 6

Annotations 1

Signed technical comments from index contributors. Not a discussion forum — annotations question or contextualise the result, and the data team replies where a reply is warranted.

peak_integrator18 Mar 2025

Resolution to the nearest named impurity is reported on this record with no verdict attached, which is the correct handling. A threshold on that figure would penalise compounds for their own impurity profiles.

Section 7

Related records

Same batch — lot GSP-2501-G3708 n=12

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2025-019137	GSP-2501-G3708	PeptideMeter	2025-Q1	98.06	4.56	—	Buyer-sourced	0	PASS
AX-2025-019138	GSP-2501-G3708	Janoshik	2025-Q1	98.29	4.52	—	Buyer-sourced	0	PASS
AX-2025-019139	GSP-2501-G3708	Medutest	2025-Q1	99.06	3.60	—	Supplier-supplied	1	MARGINAL
AX-2025-019140	GSP-2501-G3708	PeptideMeter	2025-Q1	98.23	4.03	—	Buyer-sourced	0	PASS
AX-2025-019141	GSP-2501-G3708	VendorInvestigate	2025-Q1	98.13	4.76	—	Buyer-sourced	0	PASS
AX-2025-019143	GSP-2501-G3708	PeptideMeter	2025-Q1	98.07	4.59	—	Buyer-sourced	0	PASS
AX-2025-019144	GSP-2501-G3708	Kestrel	2025-Q1	98.34	4.24	—	Buyer-sourced	0	PASS
AX-2025-019145	GSP-2501-G3708	Janoshik	2025-Q1	98.43	4.76	95.3	Laboratory-retained	0	PASS
AX-2025-019146	GSP-2501-G3708	Medutest	2025-Q1	98.28	4.59	95.0	Buyer-sourced	0	PASS
AX-2025-019147	GSP-2501-G3708	PeptideMeter	2025-Q1	98.15	4.04	95.2	Buyer-sourced	0	PASS
AX-2025-019148	GSP-2501-G3708	PeptideMeter	2025-Q1	98.29	3.94	—	Buyer-sourced	0	PASS

Batch rollup and reproducibility assessment →

Cross-sections

Other recent Tesamorelin records in the index.
Report	Supplier	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-042704	ERP	ERP-2604-W9463	Janoshik	2026-Q3	99.02	4.08	—	Buyer-sourced	1	MARGINAL
AX-2026-043598	PPG	PPG-2608-A6835	Kestrel	2026-Q3	98.91	2.56	100.3	Buyer-sourced	1	FAIL
AX-2026-043597	PPG	PPG-2608-A6835	Janoshik	2026-Q3	98.54	1.15	—	Buyer-sourced	0	PASS
AX-2026-043596	PPG	PPG-2608-A6835	PeptideMeter	2026-Q3	98.74	1.83	105.1	Buyer-sourced	1	MARGINAL
AX-2026-043380	WXT	WXT-2601-A2974	Medutest	2026-Q1	97.17	3.06	91.5	Buyer-sourced	0	PASS
AX-2025-021018	WXT	WXT-2505-B3939	Janoshik	2025-Q3	96.86	3.77	95.9	Buyer-sourced	1	FAIL
AX-2025-019141	GSP	GSP-2501-G3708	VendorInvestigate	2025-Q1	98.13	4.76	—	Buyer-sourced	0	PASS
AX-2025-019137	GSP	GSP-2501-G3708	PeptideMeter	2025-Q1	98.06	4.56	—	Buyer-sourced	0	PASS

Other recent GSP records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-041831	Survodutide	GSP-2603-E3156	Kestrel	2026-Q3	99.91	5.50	93.2	Buyer-sourced	0	PASS
AX-2026-041836	Survodutide	GSP-2603-E3156	Janoshik	2026-Q3	98.65	5.34	90.3	Buyer-sourced	0	PASS
AX-2026-041837	Survodutide	GSP-2603-E3156	Janoshik	2026-Q3	98.33	5.37	—	Buyer-sourced	0	PASS
AX-2026-041833	Survodutide	GSP-2603-E3156	Janoshik	2026-Q3	98.08	4.91	99.3	Buyer-sourced	0	PASS
AX-2026-041832	Survodutide	GSP-2603-E3156	VendorInvestigate	2026-Q3	98.01	5.14	99.5	Buyer-sourced	0	PASS
AX-2026-041835	Survodutide	GSP-2603-E3156	Nordanalyt	2026-Q3	98.34	5.74	89.0	Buyer-sourced	1	MARGINAL
AX-2026-041834	Survodutide	GSP-2603-E3156	VendorInvestigate	2026-Q3	97.92	5.95	—	Buyer-sourced	0	PASS
AX-2026-041838	Survodutide	GSP-2603-E3156	PeptideMeter	2026-Q3	98.30	5.01	102.4	Buyer-sourced	0	PASS