SHORT DESCRIPTION: Increlex is a brand name (U.S.) for injectable IGF-1 (Insulin-like Growth Factor 1), manufactured by Tercica Inc. Mecasermin, which is the given generic name for rhIGF-1, was approved by the U.S. Food and Drug Administration in August 2005 for the treatment of growth deficiency in children. It is specifically indicated for severe primary IGF-1 deficiency (Primary IGFD), which is characterized by a failure to produce normal levels of IGF-1 due to inefficiencies in the Growth Hormone IGF-1 axis. The recommended starting dose for Increlex is .04 to .08 mg/kg, which is given twice per day. If this is well tolerated for one week the dose may be increased by .04 mg/kg per injection, to a maximum of .12 mg/kg (twice daily). Doses greater than 0.12 mg/kg twice daily are not recommended clinically, due to potential hypoglycemic effects. For the same reason, an upper ceiling of safety/comfort will be reached with most bodybuilders (this is not "more = better" type of drug). This will likely be extended over the .12 mg/kg recommendation (despite the recommendations against by the manufacturer) with some adventurous athletes, as they learn to exploit the hypoglycemic effects of IGF-1, taking it with a high level of simple carbohydrates during the post-training window. Despite the temptation, one should never begin using this drug at a high dosage! Minor side effects are intra cranial hypertension, which occurred in three subjects. In two subjects the events resolved without ceasing the drug, while in a third a short break and resumption at a lower dose resolved the issue. Mild elevations in the serum AST and LDH were found in a significant number of patients, but they were not significant enough to discontinue therapy.

LONG DESCRIPTION: Increlex is a brand name (U.S.) for injectable IGF-1 (Insulin-like Growth Factor 1), manufactured by Tercica Inc. of Brisbane California. Tercica licenses this technology from Genentech, which was the first company to sell a synthetically manufactured Human Growth Hormone product in the United States (Protropin). Like Human Growth Hormone, IGF-1 is a delicate and complex hormone. It consists of 70 amino acids in a single chain, with three disulfide bridges and a molecular weight of 7649 Daltons. Tercica's rhIGF-1 is produced by recombinant DNA technology, where it is synthesized by E. coli bacteria that have been modified by the addition of the human IGF-1 gene. The resulting product is identical to the endogenous IGF-1 protein, with all 70 amino acids in the proper sequence (unlike early high products like Protropin, which use slight variants of the active hormone).

Mecasermin, which is the given generic name for rhIGF-1, was approved by the U.S. Food and Drug Administration in August 2005 for the treatment of growth deficiency in children. It is specifically indicated for severe primary IGF-1 deficiency (Primary IGFD), which is characterized by a failure to produce normal levels of IGF-1 due to inefficiencies in the Growth Hormone IGF-1 axis. Such patients typically have normal or even high levels of Growth Hormone, but their bodies do not respond to it with the normal production of IGF-1. It is also indicated for the treatment of certain patients who have developed antibodies to Growth Hormone. In either case, the patient is not properly responsive to Growth Hormone therapy, making IGF-1 a very promising alternative medication. Tercica was granted Orphan Drug status for the use of Mecasermin to treat Primary IGFD, which means they have a market protected from competition (generic Mecasermin products) for a period of seven years.

Insulin-like Growth Factor-1 is a primary mediator of Growth Hormone's actions in the human body. GH binds to Growth Hormone receptors in the liver and peripheral tissues, and stimulates the synthesis and secretion of IGF-1. IGF-1, in turn, is the hormone actually responsible for the positive effects GH therapy has on skeletal muscle mass, whole body cell/organ growth, bone density, and linear (statural) growth. IGF-1 is also responsible for the known effect of Growth Hormone therapy on carbohydrate metabolism, namely reducing hepatic glucose production and stimulating peripheral glucose utilization. A good deal of research is being given to IGF-1 drugs in the treatment of certain forms of diabetes, and in December 2003 the FDA even granted Insmed Orphan Drug status for the use of Mecasermin Rinfibate (a similar medication not yet on the market) for the treatment of extreme Insulin resistance. Overall, Increlex will offer many of the same therapeutic benefits that are known of Growth Hormone. For our purposes this, of course, includes the support of muscle growth in adulthood, though this is not yet an approved use of the drug. Perhaps at some point we will see it approved for some newly recognized adult IGF-1 deficiency, like rHGH was for adult GH deficiency. Until then, it will likely remain an expensive drug, marketed exclusively to a small population of patients.

Although IGF-1 is a primary mediator of the effects, it is important to point out that it is not the sole mediator of them. GH does have some inherent effects in the body. The most notably of these is an effect of body fat deposition. GH has a Strong lipolytic effect, which can be so direct and measurable that patients commonly notice a reduction of fat even around the site of injection. This trait is lacking in IGF-1. In fact, a common documented side effect of Increlex therapy is lipohypertrophy (fat gain) around the site of injection's IGF-1 drug like this will, therefore, offer muscle growth benefits like (or better than) rHGH, but will not offer the same strong benefits on fat loss and muscle definition. These agents are more appropriately used during bulking phases of training, whereas Growth Hormone preparations will, likely, remain the preferred drugs of the "Growth Hormone and Related" class for cutting cycles.

Increlex comes as an aqueous solution, with each milliliter containing l0 mg of IGF-1 protein. It is intended to be administered subcutaneously, usually under small pinches of skin on the abdominal or thigh areas (like rHGH is usually administered). Due to the very fast metabolism of free IGF-1, the drug has a very short half-life in the body. Tercica's dosing recommendations call for an individual optimal dose to be determined, which is always based on twice daily application. The recommended starting dose is .04 to .08 mg/kg, which is given twice per day. If this is well tolerated for one week the dose may be increased by .04 mg/kg per injection, to a maximum of .12 mg/kg (twice daily). Doses greater than 0.12 mg/kg twice daily are not recommended clinically, due to potential hypoglycemic effects. For the same reason, an upper ceiling of safety/comfort will be reached with most bodybuilders (this is not "more = better" type of drug). This will likely be extended over the .12 mg/kg recommendation (despite the recommendations against by the manufacturer) with some adventurous athletes, as they learn to exploit the hypoglycemic effects of IGF-1, taking it with a high level of simple carbohydrates during the post-training window. Despite the temptation, one should never begin using this drug at a high dosage! If hypoglycemia occurs, despite adequate food intake, it is also important that the dose be reduced, for the sake of safety. Increlex should always be administered shortly before or after (20 minutes) a meal or snack as well, and never when simple carbohydrates are out of reach.

Unlike Increlex, which can be used for extended periods (years) in clinical medicine, bodybuilders would use this drug for shorter durations of 6-16 weeks. This is to minimize the potential for side effects or unwanted organ growth. As for an assessment of its general safety, we can note that medical data seems very favorable when the drug is administered correctly. During clinical studies with 71 subjects with Primary IGFD treated for a mean duration of 3.9 years, Increlex was very well tolerated, and none of the subjects withdrew from clinical study due to side effects or safety concerns. The most common side effect was hypoglycemia, which was reported by 42% of subjects on at least one occasion during therapy. This drug does, indeed, have a strong Insulin-like effect, which should be monitored. Most cases of hypoglycemia were mild, although five subjects had severe hypoglycemia requiring medical treatment, four of which experienced hypoglycemic seizures or loss of consciousness on one or more occasion. Symptomatic hypoglycemia was generally avoided when a meal or snack was consumed shortly before or after the administration of the drug. Enlargement of the tonsils occurred in 15% of patients during the first 1 to 2 years of therapy with lesser growth was noted in later years. Seven subjects required tonsillectomy.

Other minor side effects included intra cranial hypertension, which occurred in three subjects. In two subjects the events resolved without ceasing the drug, while in a third a short break and resumption at a lower dose resolved the issue. Mild elevations in the serum AST and LDH were found in a significant number of patients, but they were not significant enough to discontinue therapy. ALT elevations were occasionally noted as well, but again were not serious. Renal hypertrophy was shown to be rapid during the early years of therapy, although renal function remained normal in all patients. Elevations in cholesterol and triglycerides were observed, but remained within the upper limit of normal values. Evidence of heart enlargement was observed in a few individuals without clinical symptoms. The overall relationship between drug use and cardiac changes, however, has not yet been fully assessed. Thickening of facial soft tissues was observed in several patients, and should be monitored during therapy. Overall, the drug seems well tolerated, with a side effect profile that is not that far out of line with what we know of Growth Hormone drugs.

IGF-1 is known to be a potent stimulator of human muscle growth. We have seen drugs of this class, namely Long R3 IGF-1, work very well on very many occasions in the past. In some instances, this has been to an extent that might be called remarkable by the user. We wouldn't go so far as to call for an abandonment of steroids, however, as we still believe steroids are far more reliable and effective for the average user. The gains with IGF-l, though, are nothing to sneeze at in most cases. But with Long-R3, we also must remember that we have a synthetic compound with as of yet unverified safety in humans. It is an "experimental drug", used on animals only. We know it works on humans, but we don't have much safety data behind it. Increlex, on the other hand, is an approved drug in the U,S., and has been the subject of a great amount of research before reaching such a state. Though not yet approved for adult use, we can feel fairly comfortable with this drug. IGF-1 is admittedly a powerful "whole body" anabolic agent, and carries potential risks relating to organ growth if abused. These should never be ignored. But for those who are looking for safe and sane experimentation with an IGF-1 class drug, and would prefer an FDA approved medication over experimental compounds, you need look no further (provided you can find a way to purchase it, that is).