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Working with a Peptide Serum Contract Manufacturer
What a contract manufacturer needs from a peptide supplier — INCI form, lot COA, use level basis and lead time — and how to brief it.
Most peptide serum projects involve three parties rather than two: the brand, the contract manufacturer who fills the product, and the ingredient supplier. Most of the delays in those projects come from the handoffs between them, not from any one party being slow.
What the contract manufacturer will ask for
| Request | Why they need it | What to send |
|---|---|---|
| INCI name and declarable form | They build the label and the PIF | The inventory name, not the trade name |
| Lot COA | They hold the documentation for the batch | The certificate for the lot that will actually be used |
| Use level and carrier | They calculate the formula | Percentage of supplied material, and what it is supplied in |
| Solubility and pH behaviour | They choose the phase and the process | Practical notes at your likely pH range |
| Lead time and shelf life | They schedule production | Dispatch timing and remaining shelf life on arrival |
The three handoffs that break
1. Trade name versus INCI name. The brand briefs the manufacturer using the supplier's trade name. The manufacturer builds the label from that. The label is then wrong. This is the single most common failure, and it is fixed by putting the INCI name in the brief from the start.
2. Specification sheet versus lot COA. The manufacturer receives a generic specification sheet and treats it as the batch record. It is not. The COA for the specific lot is what belongs in the file.
3. Concentration basis. A supplier quotes “1% use level” meaning 1% of a 1% solution. The manufacturer reads it as 1% of pure peptide. The finished product is off by two orders of magnitude. Always ask what the percentage refers to.
How to brief the project so it does not stall
One page, five lines, sent to both the supplier and the manufacturer on the same day:
- Product type and target pH
- Peptide or peptides, with INCI names
- Intended use level, and the basis of that percentage
- Pack size and label language
- Target first production date
When both sides see the same five lines, the mismatches surface before the purchase order rather than after the first batch.
What to qualify in the manufacturer, not just the supplier
Ask the manufacturer two questions before you commit: what is the smallest batch they will run, and what is their changeover procedure between products. The first decides whether your launch is affordable. The second decides whether your first batch carries the previous product's residue — a real risk with low-use-level actives.
Frequently asked questions
What does a contract manufacturer need from a peptide supplier?
The INCI name in declarable form, a lot-specific COA, the use level with its basis, solubility and pH behaviour, and lead time with remaining shelf life.
Who is responsible for the label — brand or contract manufacturer?
Whoever is named as the responsible person for the finished product, which is usually the brand. The manufacturer executes the declaration, so both need the same INCI names.
What is the most common cause of a stalled peptide serum project?
A mismatch at the handoff: trade name versus INCI name, specification sheet versus lot COA, or a use-level percentage quoted on a different basis.
What is the smallest realistic batch?
It depends on the manufacturer and the filler line. Ask before you set a launch quantity, because it determines your cost per unit more than the raw material price does.
Can I send supplier documentation directly to the manufacturer?
Yes, but send the lot COA rather than a generic specification sheet, and include the INCI name and the basis of the use level in the same message.