Twelve Month Follow-Up of CP0108

percentage of subjects who had achieved 100% clearance at Visit 6 (Week 12) in CP0108, that have one or more previously treated (as part of CP0108) AK lesion(s) present in the Treatment Area at any visit during CP0108A follow-up

the time from Week 12 (in the DUSA-CP0108 study) to the visit at which a previously treated and cleared lesion recurs. If a subject begins or receives treatment for previously cleared AK lesions in the Treatment Area between scheduled visits, the date the treatment started will be the end of treatment response, or, if the start date is unknown, the visit prior to starting the new treatment will be the end of treatment response.

the proportion of lesions that were CR at Week 12 in CP0108 that are visible or palpable at Visit 10, will be determined for all ALA-PDT treated subjects who have at least one AK designated as "clear" at Week 12 in the DUSA-CP0108 study.

the time from Week 12 (in the DUSA-CP0108 study) to the visit at which the AK lesion recurs for all ALA-PDT treated subjects who have at least one AK designated as "clear" at Week 12 in the DUSA-CP0108 study. If a previously cleared lesion receives treatment between scheduled visits, the date the treatment started will be the end of treatment response for that lesion, or, if the start date is unknown, the visit prior to starting the new treatment will be the end of treatment response.

HYPERPIGMENTATION SCALE Grade 0 = No hyperpigmentation Grade 1 = Light hyperpigmentation involving small areas Grade 2 = Moderate hyperpigmentation involving small areas; light hyperpigmentation involving moderate areas Grade 3 = Moderate hyperpigmentation involving moderate sized areas; light hyperpigmentation involving large areas; small areas of marked hyperpigmentation Grade 4 = Marked hyperpigmentation involving moderate or large sized areas

HYPERPIGMENTATION SCALE Grade 0 = No hyperpigmentation Grade 1 = Light hyperpigmentation involving small areas Grade 2 = Moderate hyperpigmentation involving small areas; light hyperpigmentation involving moderate areas Grade 3 = Moderate hyperpigmentation involving moderate sized areas; light hyperpigmentation involving large areas; small areas of marked hyperpigmentation Grade 4 = Marked hyperpigmentation involving moderate or large sized areas

HYPERPIGMENTATION SCALE Grade 0 = No hyperpigmentation Grade 1 = Light hyperpigmentation involving small areas Grade 2 = Moderate hyperpigmentation involving small areas; light hyperpigmentation involving moderate areas Grade 3 = Moderate hyperpigmentation involving moderate sized areas; light hyperpigmentation involving large areas; small areas of marked hyperpigmentation Grade 4 = Marked hyperpigmentation involving moderate or large sized areas

HYPERPIGMENTATION SCALE Grade 0 = No hyperpigmentation Grade 1 = Light hyperpigmentation involving small areas Grade 2 = Moderate hyperpigmentation involving small areas; light hyperpigmentation involving moderate areas Grade 3 = Moderate hyperpigmentation involving moderate sized areas; light hyperpigmentation involving large areas; small areas of marked hyperpigmentation Grade 4 = Marked hyperpigmentation involving moderate or large sized areas

HYPERPIGMENTATION SCALE Grade 0 = No hyperpigmentation Grade 1 = Light hyperpigmentation involving small areas Grade 2 = Moderate hyperpigmentation involving small areas; light hyperpigmentation involving moderate areas Grade 3 = Moderate hyperpigmentation involving moderate sized areas; light hyperpigmentation involving large areas; small areas of marked hyperpigmentation Grade 4 = Marked hyperpigmentation involving moderate or large sized areas

HYPOPIGMENTATION SCALE Grade 0 = No hypopigmentation Grade 1 = Light hypopigmentation involving small areas Grade 2 = Moderate hypopigmentation involving small areas; light hypopigmentation involving moderate areas Grade 3 = Moderate hypopigmentation involving moderate sized areas; light hypopigmentation involving large areas; small areas of marked hypopigmentation

HYPOPIGMENTATION SCALE Grade 0 = No hypopigmentation Grade 1 = Light hypopigmentation involving small areas Grade 2 = Moderate hypopigmentation involving small areas; light hypopigmentation involving moderate areas Grade 3 = Moderate hypopigmentation involving moderate sized areas; light hypopigmentation involving large areas; small areas of marked hypopigmentation

HYPOPIGMENTATION SCALE Grade 0 = No hypopigmentation Grade 1 = Light hypopigmentation involving small areas Grade 2 = Moderate hypopigmentation involving small areas; light hypopigmentation involving moderate areas Grade 3 = Moderate hypopigmentation involving moderate sized areas; light hypopigmentation involving large areas; small areas of marked hypopigmentation

HYPOPIGMENTATION SCALE Grade 0 = No hypopigmentation Grade 1 = Light hypopigmentation involving small areas Grade 2 = Moderate hypopigmentation involving small areas; light hypopigmentation involving moderate areas Grade 3 = Moderate hypopigmentation involving moderate sized areas; light hypopigmentation involving large areas; small areas of marked hypopigmentation

HYPOPIGMENTATION SCALE Grade 0 = No hypopigmentation Grade 1 = Light hypopigmentation involving small areas Grade 2 = Moderate hypopigmentation involving small areas; light hypopigmentation involving moderate areas Grade 3 = Moderate hypopigmentation involving moderate sized areas; light hypopigmentation involving large areas; small areas of marked hypopigmentation

Erythema Scale - Grade 0 = None Grade 1 = Minimal - barely perceptible erythema Grade 2 = Mild - predominantly minimal erythema (pink) in the treated area with or without a few isolated areas of more intense erythema Grade 3 = Moderate - predominantly moderate erythema (red) in the treated area with or without a few isolated areas of intense erythema (bright red) Grade 4 = Severe - predominantly intense erythema (bright red) in the treated area with or without a few isolated areas of very intense (fiery red) erythema

Erythema Scale - Grade 0 = None Grade 1 = Minimal - barely perceptible erythema Grade 2 = Mild - predominantly minimal erythema (pink) in the treated area with or without a few isolated areas of more intense erythema Grade 3 = Moderate - predominantly moderate erythema (red) in the treated area with or without a few isolated areas of intense erythema (bright red) Grade 4 = Severe - predominantly intense erythema (bright red) in the treated area with or without a few isolated areas of very intense (fiery red) erythema

Erythema Scale - Grade 0 = None Grade 1 = Minimal - barely perceptible erythema Grade 2 = Mild - predominantly minimal erythema (pink) in the treated area with or without a few isolated areas of more intense erythema Grade 3 = Moderate - predominantly moderate erythema (red) in the treated area with or without a few isolated areas of intense erythema (bright red) Grade 4 = Severe - predominantly intense erythema (bright red) in the treated area with or without a few isolated areas of very intense (fiery red) erythema

Erythema Scale - Grade 0 = None Grade 1 = Minimal - barely perceptible erythema Grade 2 = Mild - predominantly minimal erythema (pink) in the treated area with or without a few isolated areas of more intense erythema Grade 3 = Moderate - predominantly moderate erythema (red) in the treated area with or without a few isolated areas of intense erythema (bright red) Grade 4 = Severe - predominantly intense erythema (bright red) in the treated area with or without a few isolated areas of very intense (fiery red) erythema

Erythema Scale - Grade 0 = None Grade 1 = Minimal - barely perceptible erythema Grade 2 = Mild - predominantly minimal erythema (pink) in the treated area with or without a few isolated areas of more intense erythema Grade 3 = Moderate - predominantly moderate erythema (red) in the treated area with or without a few isolated areas of intense erythema (bright red) Grade 4 = Severe - predominantly intense erythema (bright red) in the treated area with or without a few isolated areas of very intense (fiery red) erythema

EDEMA SCALE Grade 0 = None Grade 1 = Minimal - scant, rare edema Grade 2 = Mild - easily seen edema, minimally palpable, involving up to 1/3 of the treatment area Grade 3 = Moderate - easily seen edema and typically palpable, involving between 1/3 to 2/3 of the treatment area Grade 4 = Severe - easily seen edema, indurated in some areas, involving over 2/3 of the treatment area

EDEMA SCALE Grade 0 = None Grade 1 = Minimal - scant, rare edema Grade 2 = Mild - easily seen edema, minimally palpable, involving up to 1/3 of the treatment area Grade 3 = Moderate - easily seen edema and typically palpable, involving between 1/3 to 2/3 of the treatment area Grade 4 = Severe - easily seen edema, indurated in some areas, involving over 2/3 of the treatment area

EDEMA SCALE Grade 0 = None Grade 1 = Minimal - scant, rare edema Grade 2 = Mild - easily seen edema, minimally palpable, involving up to 1/3 of the treatment area Grade 3 = Moderate - easily seen edema and typically palpable, involving between 1/3 to 2/3 of the treatment area Grade 4 = Severe - easily seen edema, indurated in some areas, involving over 2/3 of the treatment area

EDEMA SCALE Grade 0 = None Grade 1 = Minimal - scant, rare edema Grade 2 = Mild - easily seen edema, minimally palpable, involving up to 1/3 of the treatment area Grade 3 = Moderate - easily seen edema and typically palpable, involving between 1/3 to 2/3 of the treatment area Grade 4 = Severe - easily seen edema, indurated in some areas, involving over 2/3 of the treatment area

EDEMA SCALE Grade 0 = None Grade 1 = Minimal - scant, rare edema Grade 2 = Mild - easily seen edema, minimally palpable, involving up to 1/3 of the treatment area Grade 3 = Moderate - easily seen edema and typically palpable, involving between 1/3 to 2/3 of the treatment area Grade 4 = Severe - easily seen edema, indurated in some areas, involving over 2/3 of the treatment area

STINGING AND BURNING SCALE Grade 0 = None Grade 1 = Minimal, barely perceptible -tolerable and little discomfort Grade 2 = Moderate - tolerable, but causes some discomfort Grade 3 = Severe - very uncomfortable or intolerable

STINGING AND BURNING SCALE Grade 0 = None Grade 1 = Minimal, barely perceptible -tolerable and little discomfort Grade 2 = Moderate - tolerable, but causes some discomfort Grade 3 = Severe - very uncomfortable or intolerable

STINGING AND BURNING SCALE Grade 0 = None Grade 1 = Minimal, barely perceptible -tolerable and little discomfort Grade 2 = Moderate - tolerable, but causes some discomfort Grade 3 = Severe - very uncomfortable or intolerable

STINGING AND BURNING SCALE Grade 0 = None Grade 1 = Minimal, barely perceptible -tolerable and little discomfort Grade 2 = Moderate - tolerable, but causes some discomfort Grade 3 = Severe - very uncomfortable or intolerable

STINGING AND BURNING SCALE Grade 0 = None Grade 1 = Minimal, barely perceptible -tolerable and little discomfort Grade 2 = Moderate - tolerable, but causes some discomfort Grade 3 = Severe - very uncomfortable or intolerable

SCALING AND DRYNESS SCALE Grade 0 = None Grade 1 = Minimal - barely perceptible desquamation Grade 2 = Mild - limited areas of fine desquamation in up to 1/3 of the treatment area Grade 3 = Moderate - fine desquamation involving 1/3 to 2/3 of the treatment area or limited areas of coarser scaling Grade 4 = Severe - coarser scaling involving more than 2/3 of the treatment area or limited areas of very coarse scaling

SCALING AND DRYNESS SCALE Grade 0 = None Grade 1 = Minimal - barely perceptible desquamation Grade 2 = Mild - limited areas of fine desquamation in up to 1/3 of the treatment area Grade 3 = Moderate - fine desquamation involving 1/3 to 2/3 of the treatment area or limited areas of coarser scaling Grade 4 = Severe - coarser scaling involving more than 2/3 of the treatment area or limited areas of very coarse scaling

SCALING AND DRYNESS SCALE Grade 0 = None Grade 1 = Minimal - barely perceptible desquamation Grade 2 = Mild - limited areas of fine desquamation in up to 1/3 of the treatment area Grade 3 = Moderate - fine desquamation involving 1/3 to 2/3 of the treatment area or limited areas of coarser scaling Grade 4 = Severe - coarser scaling involving more than 2/3 of the treatment area or limited areas of very coarse scaling

SCALING AND DRYNESS SCALE Grade 0 = None Grade 1 = Minimal - barely perceptible desquamation Grade 2 = Mild - limited areas of fine desquamation in up to 1/3 of the treatment area Grade 3 = Moderate - fine desquamation involving 1/3 to 2/3 of the treatment area or limited areas of coarser scaling Grade 4 = Severe - coarser scaling involving more than 2/3 of the treatment area or limited areas of very coarse scaling

SCALING AND DRYNESS SCALE Grade 0 = None Grade 1 = Minimal - barely perceptible desquamation Grade 2 = Mild - limited areas of fine desquamation in up to 1/3 of the treatment area Grade 3 = Moderate - fine desquamation involving 1/3 to 2/3 of the treatment area or limited areas of coarser scaling Grade 4 = Severe - coarser scaling involving more than 2/3 of the treatment area or limited areas of very coarse scaling

OOZING/VESICULATION/CRUSTING Grade 0 = None Grade 1 = Minimal - a single area of oozing, vesiculation or crusting 3 mm diameter or less in size Grade 2 = Mild - two to four areas of oozing, vesiculation or crusting 3 mm diameter or less in size OR a single area larger than 3 mm diameter in size Grade 3 = Moderate - more than a single area of oozing, vesiculation or crusting larger than 3 mm diameter in size or more than four areas of 3 mm diameter or less in size Grade 4 = Severe - any degree of oozing, vesiculation or crusting greater than (3) above

OOZING/VESICULATION/CRUSTING Grade 0 = None Grade 1 = Minimal - a single area of oozing, vesiculation or crusting 3 mm diameter or less in size Grade 2 = Mild - two to four areas of oozing, vesiculation or crusting 3 mm diameter or less in size OR a single area larger than 3 mm diameter in size Grade 3 = Moderate - more than a single area of oozing, vesiculation or crusting larger than 3 mm diameter in size or more than four areas of 3 mm diameter or less in size Grade 4 = Severe - any degree of oozing, vesiculation or crusting greater than (3) above

OOZING/VESICULATION/CRUSTING Grade 0 = None Grade 1 = Minimal - a single area of oozing, vesiculation or crusting 3 mm diameter or less in size Grade 2 = Mild - two to four areas of oozing, vesiculation or crusting 3 mm diameter or less in size OR a single area larger than 3 mm diameter in size Grade 3 = Moderate - more than a single area of oozing, vesiculation or crusting larger than 3 mm diameter in size or more than four areas of 3 mm diameter or less in size Grade 4 = Severe - any degree of oozing, vesiculation or crusting greater than (3) above

OOZING/VESICULATION/CRUSTING Grade 0 = None Grade 1 = Minimal - a single area of oozing, vesiculation or crusting 3 mm diameter or less in size Grade 2 = Mild - two to four areas of oozing, vesiculation or crusting 3 mm diameter or less in size OR a single area larger than 3 mm diameter in size Grade 3 = Moderate - more than a single area of oozing, vesiculation or crusting larger than 3 mm diameter in size or more than four areas of 3 mm diameter or less in size Grade 4 = Severe - any degree of oozing, vesiculation or crusting greater than (3) above

OOZING/VESICULATION/CRUSTING Grade 0 = None Grade 1 = Minimal - a single area of oozing, vesiculation or crusting 3 mm diameter or less in size Grade 2 = Mild - two to four areas of oozing, vesiculation or crusting 3 mm diameter or less in size OR a single area larger than 3 mm diameter in size Grade 3 = Moderate - more than a single area of oozing, vesiculation or crusting larger than 3 mm diameter in size or more than four areas of 3 mm diameter or less in size Grade 4 = Severe - any degree of oozing, vesiculation or crusting greater than (3) above