GOURI and the Other Skin Boosters — What Separates It from Rejuran, Juvelook and Radiesse

Look especially at the last column. Most of the collagen booster class, GOURI included, does not dissolve with hyaluronidase, unlike hyaluronic acid fillers. Whether there is a means of reversal if you are unhappy is one of the conditions that ought to weigh most heavily at the stage of choosing a treatment.

Products sitting on the same shelf passed through different gates to reach the market. That is the actual cause of the difference in data thickness.

Products approved as medical devices needed human clinical trial data for that approval. Rejuran (PN) is one of these — it passed a phase 3 trial, randomised, double-blinded, split-face, active-controlled, with 70 people analysed. But the scope of what that trial demonstrated has to be read precisely. The primary endpoint was an improvement rate on photographic assessment and the comparator was a hyaluronic acid product rather than placebo, so what the trial showed extends to “not inferior to a hyaluronic acid product” (improvement 95.7% versus 94.3%, a difference of 1.4 percentage points, meeting a non-inferiority margin of −15%).

Products distributed as human tissue follow a different law. hADM (Celldem, Rituo) is human tissue under the Act on Safety and Management of Human Tissue, so it is distributed on a tissue bank licence alone and there was no legal obligation to submit clinical trial data before marketing.

Some are distributed as cosmetics. The exosome preparations circulating in Korea are cosmetics rather than pharmaceuticals, and applying them topically versus introducing them with a syringe or microneedle are separate acts that the MFDS and the Seoul Administrative Court have distinguished. The US FDA has issued a warning about injectable exosome products. Miso Clinic in Daegu uses exosome preparations only as a topical application after laser and does not place them inside the skin. The extent of the evidence is set out in how far exosome preparations have actually been confirmed.

This is the most confusing comparison. GOURI and Ellansé are the same polycaprolactone as a material, yet the thickness of their data is the exact opposite.

No study has compared the two formulations directly in humans. So transferring Ellansé’s biopsy figures and post-marketing safety figures onto GOURI is an extension without grounds. In practice this transfer is the single most frequent move in the explanations in circulation. The differences between the formulations are covered in more detail in the same polycaprolactone: what separates liquid-form from microsphere.

Nodules are what people worry about most when choosing a collagen booster. The character of the data differs by class.

“There is no number” and “0%” are different things. The absence of nodule reports for GOURI rests on a denominator far too small to be used as grounds for reassurance. The timing, character and management of nodules generally are set out in nodules after treatment.

The order in which you choose a product starts not from “which is better” but from “what is my problem”.

Approval scope differs by country and has to be read together. For Radiesse (CaHA), the Korean approval no. 10-1238 (2010-11-17) intended use includes volume on the back of the hands, while the US FDA approval history is separate — back of the hands 2015-06-04, jawline 2021-09-01, décolletage 2026-03-31. Korean approval and overseas approval are not the same thing.

One thing to add: the Korean approved intended-use wording generally describes these products as “temporary improvement of facial wrinkles in adults through physical restoration,” so collagen production is not language that falls within the scope of approval.

Written and reviewed by Lee Chi-Hak, MD, medical director of Miso Clinic in Daegu, South Korea. Every study cited above is given together with its design, its size and the limitations the authors themselves recorded, and where we could not find data, we have said that we could not find any.