MBX MBX Biosciences, Inc. Insider Trading

CMO exercises stock options, immediately sells all shares for nearly $2.7M gain; net neutral position in unprofitable biotech.

Azoulay Salomon, Chief Medical Officer of MBX Biosciences, exercised stock options and liquidated the entire resulting position on the same day for a notable profit spread: acquiring shares at roughly $10–$16 per share and selling them immediately at approximately $38 per share. This is a classic option-exercise-and-sell transaction—a common way insiders monetize compensation. The pattern itself is not unusual, but the execution matters: Salomon is disposing of shares in a company losing money and trading well below its 52-week high, while also in the third year of Form 4 filings at this company with a track record of selling (two prior sales in the 36-month window). The net zero holdings position after this filing means Salomon holds no residual equity stake, despite having just exercised options—suggesting this was a pure liquidity event rather than a vote of confidence in the company's direction. For a biotech firm burning cash, seeing an officer take profits and walk away entirely is worth noting.

CEO Hawryluk buys 18,500 MBX shares at $28.41; 2 prior MBX buys both showed +90d returns; stock now -30.9% from 52-week high amid -$21.6M net income.

P. Kent Hawryluk, the CEO, purchased 18,500 shares at $28.41, bringing his holdings to 486,777 shares (+4.0% vs pre-transaction), on 2026-03-13. His prior trade history at MBX is notable: two earlier buys on 2025-10-20 and 2025-02-04 both delivered positive 90-day returns (+100.8% and +12.9% respectively), with both timed at the 90-day inflection point where the stock subsequently rose. His cross-ticker track record reinforces this pattern: 2 prior buys averaged +105.0% 90-day return with a 100.00% win rate. The current buy occurs as MBX trades -30.9% from its 52-week high of $43.14, and the company reported a -$21.6M net income over its most recent fiscal year. The buy's proximity to the 90-day inflection point that historically preceded price appreciation—combined with the company's unprofitable fundamentals and depressed price relative to recent highs—suggests this filing merits examination of whether the CEO's prior timing accuracy repeats.

MBX CEO Hawryluk buys 20,000 shares at $13.64, expanding stake to 468,277 shares amid unprofitable fundamentals

P. Kent Hawryluk, President & CEO of MBX Biosciences, purchased 20,000 shares for $272,790.00 on 2025-10-20, increasing his holdings by 4.5% to 468,277 shares. This buy occurs at $13.64 per share, approximately 11% below the current price of $15.31 and 43.6% below the 52-week high of $24.19, yet the stock has gained 53.1% over the past 30 days. Notably, the company reported a net loss of $19,411,000.00 for its most recent full fiscal year, placing this insider accumulation in the context of negative profitability. His single prior purchase at MBX in February 2025 exhibited similar characteristics, with a positive 90-day return of +12.9%, demonstrating a timing pattern where prior buys preceded positive returns at this ticker—a data point that captures recent momentum but does not offset the underlying operational losses.

Director Steven L. Hoerter purchases 20,000 shares of MBX at $13.25; company in loss position with $-19.4M net income

Hoerter's acquisition of 20,000 shares (20.0K shares) for $264,984.00 ($265.0K) represents a full entry position, as his holdings moved from 0 to 20,000 shares. This occurs in a company context marked by unprofitability: net income of $-19,411,000.00 ($-19.4M) over the most recent full fiscal year. The transaction price of $13.25 lies within the 52-week range of $5.79–$24.19 but 41.2% below the 52-week high, following a 42.3% gain over the preceding 30 days. The significance lies in a director's first material accumulation in a loss-making biotech firm immediately following a sharp recovery phase, warranting examination of whether fundamental improvement or strategic developments underlie the buy.

Director Heron Patrick J purchased 666,666 shares of MBX at $18.00 for $11,999,988.00 ($12.0M), expanding stake to 5,219,440 shares (+14.6%), while company reported $-19,411,000 net loss.

Director Heron Patrick J made a substantial $12.0M open-market purchase of 666,666 shares at $18.00, increasing his holdings by 14.6% from 4,552,774 to 5,219,440 shares. The purchase occurred at a price 2.9% above the current market price of $17.50, and notably within a 52-week range where the stock now stands 32.6% below its high. His cross-ticker track record shows 20 prior buys with an average 90-day return of +2.5% and a 60% win rate, suggesting a historically inconsistent track record for buy timing. However, MBX Biosciences remains unprofitable with a full-year net income of $-19,411,000, meaning the fundamental backdrop is deteriorating even as the insider significantly increased exposure.

Director Pescovitz buys 7,693 shares at $5.89 amid 75.9% decline from 52-week high, stock down 31.8% in 30 days.

Director Ora H. Pescovitz purchased 7,693 shares at $5.89, increasing holdings to 24,329 shares—a 46.2% increase from pre-transaction holdings of 16,636 shares. The purchase occurred when MBX is trading at $6.27, still -75.9% from its 52-week high of $25.98 and down -31.8% over the prior 30 days and -54.2% over 90 days. The company remains unprofitable, with net income of $-18,142,000.00 for its most recent full fiscal year. The transaction represents director participation in the equity of a distressed biotech company trading substantially below historical valuation levels, occurring within a period of sharp price declines.

OrbiMed Advisors (MBX director) bought 190,672 shares for $2.0M across 4 transactions at $9.85–$10.84 in Feb 2025

OrbiMed Advisors acquired 190,672 shares (190.7K shares) totaling $2,020,755.60 ($2.0M) in four separate transactions on February 14–18, 2025, at prices ranging from $9.85 to $10.84, resulting in a blended average price of $10.60. This purchase increased holdings by 34.2% from 557.2K to 747.9K shares. At the current price of $11.22, the tranche is already in positive territory, though the stock remains 56.8% below its 52-week high of $25.98 and 32.0% down over 90 days. OrbiMed's prior two buys at MBX (September 2024) delivered 90-day returns of +18.4%, and its broader 10-buy track record across tickers shows a 100% 90-day win rate with +29.5% average return. The company is currently unprofitable (net loss $18.1M) with a market cap of $374.9M, providing context for the scale and confidence of this buy in a loss-making biotech stage. The magnitude of the purchase and the director's sustained buying pattern at this ticker and across holdings merit monitoring of upcoming corporate developments.

Director Carl L Gordon bought 190,672 shares in 4 transactions for $2,020,755.60 (blended avg $10.60)

Director Carl L Gordon made 4 separate purchases of MBX Biosciences stock totaling 190,672 shares for $2,020,755.60, increasing his holdings by 34.2% from 557,215 to 747,887 shares. The purchases spanned February 14–18, 2025, at prices ranging from $9.85 to $10.84, while the current price stands at $11.22—a position 56.8% below the 52-week high of $25.98. Gordon's cross-ticker buy track record shows 18 prior open-market purchases with an average 90-day return of +192.5% and a 61.11% win rate, and his prior two transactions at MBX (both in September 2024) each returned +18.4% over 90 days. Notably, the company is currently unprofitable with net income of $-18,142,000.00, making this a substantial capital commitment into a loss-making enterprise during a period when the stock trades significantly below recent highs.

MBX CEO Kent Hawryluk purchased 50,000 shares at $10.69; stock -56.7% from 52-week high, company posted $-18.1M net loss.

President & CEO Hawryluk purchased 50,000 shares at $10.69 on 2025-02-04, expanding his holdings from 398.3K to 448.3K shares (+12.6%). The purchase occurs in a deteriorating price environment: the stock trades -56.7% from its 52-week high of $25.98, down -30.9% over 30 days and -51.6% over 90 days. Concurrently, the company reported a net loss of $-18.1M, signaling operational challenges alongside the equity decline. The magnitude of this buy (50.0K shares for $534.5K) and the CEO's direct commitment of capital warrant investor scrutiny into whether the purchase reflects management confidence in recovery or occurs in isolation from broader business momentum.

Director GORDON CARL L buys 750,000 shares for $12,000,000 at MBX; 14 other insiders also bought in past 14 days

Director GORDON CARL L executed 2 separate purchases totaling 750,000 shares for $12,000,000.00 at $16.00 per share on 2024-09-16, converting derivative securities into common equity. This purchase occurred during a cluster period in which 14 other insiders also made acquisitions within the past 14 days, suggesting coordinated capital commitment across the insider group. The current price of $21.50 as of 2024-09-17 represents a $5.50 premium to the transaction price, though the stock is recently listed (3 trading days) and 52-week benchmarks are not yet meaningful. The concentrated buying activity across multiple insiders during this early trading period warrants monitoring to understand the drivers behind the coordinated capital deployment.