
409 ‒ Inside modern drug development: the science, economics, and regulatory hurdles
🧬 Introduction & Background
- Guest: Dr. Lloyd Klickstein, former Novartis researcher, now CEO/CSO of several biotech companies.
- Topic: The entire drug development process – from idea to approval – illustrated with the case of Bimagrumab.
🔬 Fundamentals of Drug Development
- Indications & Strategy:
- Two approaches: incremental improvements (e.g., oral vs. injectable) vs. true innovations for unmet medical needs.
- Lloyd starts with a list of ~7,000 unaddressed clinical indications and prioritizes by medical need.
- Molecule Classes:
- Small Molecules (chemical compounds)
- Biologics (antibodies, peptides, soluble receptors)
- Gene therapies & Medical devices (each with separate FDA regulations).
- Patents & Exclusivity:
- Patents grant a limited monopoly (20 years from filing, effectively ~10–15 years of market exclusivity).
- Companies can also rely on trade secrets (e.g., Armour Thyroid, Acthar Gel).
- Patent stacking (active ingredient, formulation, manufacturing process, device) extends protection.
🧪 From Target to Clinic (Preclinical)
- Target Identification: Example: muscle weakness (sarcopenia). Problem: endpoints like falls are hard to measure – an accelerometer patch detected only 17% of real falls.
- Target Choice: The activin receptor type 2 – inhibition leads to massive muscle hypertrophy in rodents (blocking myostatin and activin).
- Molecule Format: Because myostatin/activin bind extremely tightly to the receptor, biologics (antibodies) are required, not small molecules.
- Screening & Optimization:
- Phage display: thousands of antibodies tested; candidates must have higher affinity than natural ligands.
- Decision for Bimagrumab (fully human antibody against ActRIIA/B).
- Animal Studies:
- In mice: ~30% increase in muscle mass and improved strength.
- In rats: cardiac hypertrophy proportional to body size; no safety signals.
- Toxicology & DMPK: Standard safety studies in rodents and primates before first human use.
👥 Clinical Development of Bimagrumab
- Phase I (Healthy Volunteers):
- Older healthy subjects (target population sarcopenia).
- Doses up to 50–100 mg/kg; endpoints: muscle mass (DXA/MRI), blood enzymes. Side effects: muscle cramps, acne (in younger subjects), diarrhea.
- Phase II (BELIEVE trial):
- Novartis out-licensed Bimagrumab in 2021 to Versanis Bio (later acquired by Eli Lilly).
- Design: 9-arm study combining Bimagrumab with semaglutide in sarcopenic obesity.
- Results:
- Weight loss: Up to 22–23% in the high-dose combination.
- Fat loss: 45.7% – comparable to bariatric surgery.
- Muscle mass: +4–8% (much less than in rodents).
- Function: Only modest grip strength improvement; 6-minute walk distance +9 meters.
- LDL increase: ~20% (on-target liver effect) – monitorable and treatable.
- HbA1c reduction: ~7% in type 2 diabetics.
- Significance: First medical therapy achieving fat loss on par with obesity surgery.
- Current status: Eli Lilly is analyzing data; a combination study with tirzepatide is ongoing.
🚀 Outlook: Cancer Prevention as a New Strategy
- New company (Co‑L Therapeutics): Exploits a gentle ribosomal stress inducer.
- Background: Kinase inhibitors like sorafenib can cause skin cancer because they suppress a protective cell‑death signaling cascade.
- Approach: Mild activation of this cascade may prevent tumors (especially skin cancer).
- First study: Older patients with ≥5 prior skin cancers – planned Phase 2 trial.
- Potential: May also act as a treatment for melanoma (high mutation burden).
💡 Key Takeaways
- Core insights:
- Drug development is a slow, high‑risk process (~10 years, >$1 billion) where early risk elimination is crucial.
- Biologics often have fewer off‑target toxicities than small molecules.
- Choice of clinical endpoint is critical: Bimagrumab increases muscle mass but not proportionally strength – nutrition (protein) may be a key amplifier.
- Combination with GLP‑1 agonists is the logical next step for sustainable weight loss with muscle preservation.
- Preventive medicine (e.g., cancer prevention) requires building new regulatory and reimbursement frameworks.
Lloyd Klickstein emphasizes: “The greatest value for society comes when we pursue true medical innovation – even if the path is rocky.”






