METVIX Cream Ref.[9113] Active ingredients: Methyl aminolevulinate

Pharmacotherapeutic group: Antineoplastic agent
ATC code: L01XD03

Mechanism of action

Metvix with red light in AK, BCC and Bowen’s disease

After topical application of methyl aminolevulinate, porphyrins accumulate intracellularly in the treated skin lesions. The intracellular porphyrins (including PpIX) are photoactive, fluorescing compounds and, upon light activation in the presence of oxygen, singlet oxygen is formed which causes damage to cellular compartments, in particular the mitochondria. Light activation of accumulated porphyrins leads to a photochemical reaction and thereby phototoxicity to the light- exposed target cells.

Metvix with daylight in AK

After topical application of methyl aminolevulinate, porphyrins are produced intracellularly in the treated skin lesions. The intracellular porphyrins (including PpIX) are photoactive, fluorescing compounds and, upon daylight activation in the presence of oxygen, singlet oxygen is formed which causes damage to cellular compartments, in particular the mitochondria. When Metvix is used with daylight, PpIX is continuously being produced and activated within the target cells during the 2 hours of daylight exposure creating a constant micro-phototoxic effect. Daylight may not be sufficient for Metvix daylight treatment during winter months in certain parts of Europe. Metvix daylight photodynamic therapy is feasible all year long in southern Europe, from February to October in middle Europe, and from March to October in northern Europe.

Clinical efficacy

Metvix with daylight in AK

The efficacy and safety of Metvix daylight photodynamic therapy (DL-PDT) was compared to Metvix conventional photodynamic therapy (c-PDT) in two randomised, investigator-blinded, comparative, intra-individual clinical studies conducted in Australia and Europe, including a total of 231 patients. Patients were treated on one side of the face or scalp with Metvix DL-PDT and on the contralateral side with Metvix c-PDT.

The results of both Phase III studies demonstrated that Metvix DL-PDT is similar (non-inferior) to Metvix c-PDT for treating AK lesions (on the percentage change from baseline in the number of treated lesions per side at 12 weeks after one treatment) and is significantly less painful.

In the Australian study, the percentage change from baseline in the number of mild treated lesions was 89.2% versus 92.8% for DL-PDT versus c-PDT respectively (95% CI of the mean treatment difference: [-6.8; 0.3], per protocol population). In the European study, the percentage change from baseline in the number of total (mild and moderate) treated lesions was 70.1% versus 73.6% for DL PDT versus c-PDT respectively (95% CI of the mean treatment difference: [-9.5; 2.4], per protocol population).

Metvix DL-PDT was almost painless compared to Metvix c-PDT, with a pain score (on an 11-point scale ranging from 0 to 10) of 0.8 versus 5.7 (p<0.001) in the Australian study and 0.7 versus 4.4 (p<0.001) in the European study.

In both studies, regardless of whether the weather was sunny or cloudy, efficacy was demonstrated. The maintenance of lesion response rate assessed in the Australian study was high with both treatments for patients presenting at week 24 (96% for DL-PDT and 96.6% for c-PDT).