Calorad
Calorad is a liquid protein weight loss supplement which was first introduced to the US and Canadian marketplace in 1984.  It has been advertised on both television and radio.
Calorad is a liquid dietary supplement composed primarily of 3,000 mg (3 grams) of Type II hydrolyzed collagen (hydrolysate) from either beef (bovine) or tuna (marine) sources and 8 mg of aloe vera, both of which are listed as active ingredients.  The supplement label lists that it is fat-free and carbohydrate-free and that 1 serving (1/2 ounce) provides 3 grams of protein and 10 calories.  It also comes in a Kosher formulation.   The primary claim made for the product is that regular use causes weight loss without loss of lean muscle mass.  While weight loss and body fat reduction can be achieved simply by following the labeled instruction to avoid eating within three hours prior to sleep, most individuals following this regimen alone are not successful in accomplishing long-term weight loss.
Although the manufacturer does not make claims for Calorad in the treatment or cure of disease, the manufacturer does cite published clinical trials conducted with Type II hydrolyzed collagen (collagen hydrolysate), the primary ingredient in Calorad: 
Osteoarthritis and Osteoporosis:
Type II hydrolyzed collagen (collagen hydrolysate) in Osteoarthritis and Osteoporosis, 
Rheumatoid arthritis: Type II hydrolyzed collagen in Rheumatoid Arthritis,
Autoimmune Disease and Rheumatoid Arthritis: Type II collagen in Oral desensitization in the treatment of human immune diseases including Rheumatoid Arthritis, and 
Fibromyalgia: Type II collagen (collagen hydrolysat) and its effect on Symptoms of Chronic Fibromyalgia and Temporomandibular Joint Pain.
The manufacturer claims that 40% of subjects will lose weight within 1 month, 75% after 2 months and 87% after 3 months.  The manufacturer offers a 30-day satisfaction guarantee which is posted on the manufacturer's website.  In support of these claims, Essentially Yours Industries cites a clinical study of Calorad (also unpublished and non-peer reviewed) by Joel B. Lao, MD.  Dr. Lao is a Doctor of Internal Medicine, and medical consultant in the Philippines who studied the effects of Calorad and its effect on overweight and/or obese individuals. The subjects included 50 overweight or obese individuals who were observed over a 90-day period. One bottle of Calorad was provided to each of the subjects every month for a 3-month period. In month 1, the average weight loss was 5.7 pounds. By month 3, subjects had an average reduction of 10 pounds, and an average inch loss at the waist of 3 inches.
The claim that Calorad builds or maintains lean muscle mass without any increasing demand on the user's musculature is based upon an unpublished and non-peer reviewed study by Davis et al in which 300 subjects between the ages of 17-77 years, were followed for 1 year and most of whom lost weight (an average of 3.75 pounds per month) but maintained lean muscle mass.  Rena Davis holds a Master of Science (MSc) and is a practicing Clinical Nutritionist and former Biochemist.  Davis states: "We also found that in the entire group, less than 0.6, or less than 1 per cent, had any loss of lean muscle mass. And 36 per cent of the group actually gained lean muscle mass during that time."
The manufacturer (Essentially Yours Industries) states that most subjects on a weight loss regimen lose lean muscle mass along with fat and water weight, so that maintaining lean muscle mass is a benefit seen with Calorad users.
Rationale for Collagen use for Weight Loss:
There is a precedent for liquid collagen use to elicit weight loss.  The US Patent database lists a 30-year-old patent entitled: 
Method of treating obesity by the oral administration of a predigested protein composition,
US Patent #4,042,687 which was filed in June of 1976 by Gans et al (who are not associated with Essentially Yours Industries, the manufacturer of Calorad). This patent describes much of the science around liquid collagen use for weight loss, and the scientific rationale behind the use of liquid collagen for weight loss.  Results gleaned from this early study also underscored the importance of not using collagen as the sole source of nutrition (a caution listed on the bottle of Calorad today).
When first introduced, the manufacturer claimed that Calorad could cause the user to "lose weight while you sleep", repair joints, and prevent or reduce the symptoms of arthritis.  The manufacturer has since dropped these claims because they are "medical treatment claims" and require a drug treatment classification approved by the FDA, and are usually only granted  following submission of large clinical trials similar to those conducted by pharmaceutical companies in substantiation of these claims.  Essentially Yours Industries has not conducted this type of rigorous trial on Calorad in support of such claims. The manufacurer has replaced these claims with the current claim that Calorad "promotes sleep and improves the health and appearance of hair, nails and skin" (all of which are not medical treatment claims).
Calorad has not been evaluated by the US Food and Drug Administration, and all marketing materials related to the product carry a disclaimer to the effect that it is nothing more than "a food supplement and is not intended to diagnose, treat, cure, or prevent any disease."