Egrifta

Tesamorelin, sold as Egrifta (original 2010 launch), Egrifta SV (2019), and Egrifta WR (2025) by Theratechnologies, is a synthetic version of growth hormone-releasing hormone approved for reducing excess belly fat in HIV patients with lipodystrophy. It launched in late 2010 under BLA022505 and remains the only drug specifically labeled for this niche endocrine indication [1]. Theratechnologies reported approximately $73M annualized revenue in 2025 (H1 2025: $36.8M), most of it from the Egrifta franchise, before being acquired by Future Pak's CB Biotechnology subsidiary for $3.01/share plus a contingent value right of up to $1.19/share; the deal closed September 25, 2025 and the company was delisted from NASDAQ and TSX [10]. Tesamorelin is no longer a standalone public-market story. The interesting wedge for the next decade is not the HIV-lipodystrophy market itself, which is slowly shrinking as antiretroviral regimens improve, but whether GHRH agonism can be repositioned for fatty liver disease, where Stanley and Grinspoon at Mass General published a randomized trial showing approximately 32% reduction in hepatic fat fraction with tesamorelin versus no change on placebo over 12 months [8].

FDA-approved under BLA022505. The original Egrifta approval came on November 10, 2010 for the reduction of excess abdominal fat in HIV-infected adults with lipodystrophy [1]. Theratechnologies subsequently gained approval for Egrifta SV on October 19, 2019 (the F4 single-vial reformulation that simplified reconstitution) [11] and Egrifta WR on March 25, 2025 (the F8 formulation, which only requires weekly reconstitution and uses less than half the administration volume of Egrifta SV) [12]. Administration is daily subcutaneous injection. The label explicitly states tesamorelin is not indicated for weight management and has a weight-neutral effect, which cleanly separates it from the GLP-1 anti-obesity wave [1]. Long-term cardiovascular safety has not been established, and the label directs clinicians to reassess continuation in patients who do not show visceral fat reduction. No generic peptide or biosimilar has been approved or publicly filed against tesamorelin. The drug is on market with no current supply restrictions, though it requires reconstitution and patients commonly report administration difficulty. FAERS data (FDA Adverse Event Reporting System) shows 1,508 total reports with 20.5% classified as serious; the dominant signals are dose omission (278 reports), incorrect administration (164), product preparation issues (121), and injection site reactions, rather than systemic toxicity [5].

Tesamorelin is a synthetic version of growth hormone-releasing hormone (GHRH), the brain signal that tells the pituitary to release growth hormone in pulses. In HIV-associated lipodystrophy, long-term antiretroviral therapy (particularly older regimens built on stavudine, zidovudine, and early protease inhibitors) scrambles normal fat distribution: subcutaneous fat melts off the face and limbs while visceral fat accumulates deep in the abdomen, wrapped around organs. That visceral fat is not cosmetic. It is metabolically active tissue that drives insulin resistance, dyslipidemia, and elevated cardiovascular risk. By pulsing GHRH through tesamorelin, the pituitary releases endogenous growth hormone in a pattern that mimics the body's natural rhythms, rather than the constant flood that comes from injecting recombinant growth hormone directly [1]. Growth hormone then promotes lipolysis (the breakdown of stored fat for energy), with a preference for visceral depots. That preference is mechanistic, not incidental: visceral adipocytes express higher levels of growth hormone receptors and have greater lipolytic sensitivity to growth hormone than subcutaneous adipocytes, which is why GHRH agonism preferentially mobilizes the visceral fat that drives metabolic risk rather than worsening the subcutaneous wasting these patients are already experiencing. The receptor target for tesamorelin itself is GHRHR, a G protein-coupled receptor on pituitary somatotrophs that activates adenylyl cyclase and drives growth hormone gene transcription [3]. The clinical consequence is that tesamorelin preserves the body's growth hormone feedback loops, where rising IGF-1 (insulin-like growth factor 1, the downstream effector of growth hormone produced mainly by the liver) dampens further GHRH signaling, instead of overriding them. That matters because pharmacologic growth hormone dosing, the historical alternative, carries fluid retention, insulin resistance, and cardiovascular liabilities that tesamorelin largely avoids.

The key Phase 3 program supporting FDA approval (Falutz et al., NEJM 2007 and the follow-on extension) randomized HIV patients with central fat accumulation to daily tesamorelin or placebo for 26 weeks. Tesamorelin reduced visceral adipose tissue by approximately 15% versus a small placebo gain, with modest improvements in triglycerides and no clinically significant change in glucose homeostasis [4]. A 2026 meta-analysis pooled randomized trials and confirmed reductions in visceral adipose tissue and hepatic fat without consistent glucose-tolerance impairment [2]. The label flags monitoring of IGF-1 (insulin-like growth factor 1), because tesamorelin can push IGF-1 into ranges associated with acromegaly-like effects (acromegaly is a condition caused by chronic excess growth hormone that enlarges hands, feet, and facial features and increases cardiovascular risk). Clinicians are directed to interrupt dosing when IGF-1 exceeds two standard deviations above the age-adjusted mean [1]. The post-market safety database (FAERS, 1,508 reports as of the query date) is dominated by administration problems rather than drug toxicity: dose omission (278), incorrect dose administered (164), product preparation issues (121), injection site pain (130) and bruising (85), with arthralgia (88) and weight increase (96) consistent with growth hormone pharmacology [5]. Active investigator-initiated work is mapping tesamorelin's reach beyond the label: hepatic fat in HIV-associated NAFLD (Stanley et al., Lancet HIV 2019, NCT02196831, completed at MGH), which showed a roughly 32% reduction in hepatic fat fraction with tesamorelin versus no change on placebo over 12 months [8]; aging HIV cognition (NCT02572323, completed at UCSD) [7]; peripheral nerve injury recovery (NCT03150511, Johns Hopkins) [9]; and an exercise-adjunct trial for physical function in aging HIV patients (NCT06554717, MGH) [6].

Tesamorelin sits alone in its FDA-approved indication. No other drug is specifically labeled for HIV-associated lipodystrophy [1]. Recombinant human growth hormone (Serostim) was used off-label in this population for years but carried worse metabolic side effects and was never designed for visceral fat reduction. The harder commercial reality is that the addressable patient pool is shrinking. Modern antiretroviral regimens built around integrase inhibitors like dolutegravir and bictegravir, paired with second-generation NRTIs (nucleoside reverse transcriptase inhibitors) such as tenofovir alafenamide (TAF), cause far less of the fat redistribution syndrome that defined the lipodystrophy patient of the early 2000s. New HIV diagnoses today rarely develop the visceral fat phenotype tesamorelin treats. Patent exclusivity has been managed through formulation extensions for Egrifta SV (2019) and Egrifta WR (2025), but composition-of-matter protection on the original peptide is past prime, with the core tesamorelin composition patents having expired in the mid-2010s. No biosimilar peptide manufacturer has publicly filed against tesamorelin, likely because the addressable market does not justify the regulatory cost of a peptide ANDA-equivalent filing. The strategically interesting competition is not in HIV-lipodystrophy but in fatty liver disease, where resmetirom (Madrigal's Rezdiffra) and GLP-1 agonists like semaglutide and tirzepatide are reshaping care for MASH (metabolic dysfunction-associated steatohepatitis, the renamed and more sharply defined successor to NASH/NAFLD). If GHRH agonism is to find a second life it will be there, and tesamorelin would need a much larger sponsor or partnership to run a Phase 3 program against the resmetirom benchmark.

Tesamorelin's commercial story is one of careful lifecycle management in a slowly eroding niche, now under new private ownership. Theratechnologies executed two reformulations (Egrifta SV in 2019, Egrifta WR in 2025) to reduce administration friction and extend the franchise, and the drug remains the only labeled option for HIV-associated lipodystrophy [1]. The 99% probability-of-success score captures the trivial fact that the drug is approved and on label, not a forecast of commercial growth. That score will not move. What will move is the revenue trajectory, and the direction is downward absent a new indication: improved antiretrovirals are eliminating the target patient population at its source. The biggest investor-relevant change is that Theratechnologies is no longer a public company. CB Biotechnology, an affiliate of Future Pak, completed its acquisition on September 25, 2025 at $3.01/share plus a contingent value right of up to $1.19/share tied to undisclosed milestones; the shares were delisted from NASDAQ and the TSX shortly after [10]. There is no longer a public ticker to trade or a public quarterly cash position to track. The investment-relevant catalysts that remain are: (1) whether the CVR milestones get hit (terms not fully disclosed at deal close); (2) whether Future Pak invests in non-HIV indications, particularly MASH, given the Stanley/Grinspoon Lancet HIV 2019 hepatic-fat data [8]; and (3) results from the active MGH exercise-adjunct trial (NCT06554717) [6]. The base case for tesamorelin under Future Pak is slow decline of the HIV niche with cash-cow management. The upside case requires Future Pak (or a downstream partner) to fund a Phase 3 MASH program against resmetirom and GLP-1 benchmarks, which would be a substantial undertaking for a privately held specialty player. At a WAC of approximately $6,000/month (roughly $72,000 per year), tesamorelin is a high-cost specialty injectable; the revenue base is small but durable in its current indication [13].