VK2735-102 maintenance study topline (Sept 22) and upsized equity + convertible offering (Sept 23-24)
Monthly VK2735 dosing kept 85% of weight loss and every-other-week 90%, vs. 61% on placebo, with placebo-like GI tolerability. Weekly dosing hit 21.7% at 33 weeks, no plateau. Supportive for Phase 3, but small arms and exploratory endpoints. Followed by a $500M raise at $35.
What happened
On September 22, Viking reported topline results from VK2735-102, a randomized, double-blind, placebo-controlled study in roughly 180 adults with obesity (BMI 30 or higher). VK2735 is Viking's dual GLP-1/GIP agonist: it mimics two gut hormones that reduce appetite and improve blood sugar control, the same mechanism class as Eli Lilly's tirzepatide (Zepbound).
The design had two parts. First, 21 weeks of weekly injections (induction), titrated up every two weeks to final doses of 15, 17.5, 20 or 22.5 mg. Then a 12-week maintenance phase in which patients were re-randomized to every-other-week (QOW) dosing, monthly (QM) dosing, continued weekly dosing, or placebo.
The stock rallied more than 26% on the day. Two days later, Viking priced an upsized $500M financing at a 16% discount to the prior close.
The data
Induction (weeks 0 to 21)
- Weight loss of approximately 16% to 19% across VK2735 cohorts vs. roughly 0% on placebo (p<0.0001 for all cohorts)
- Placebo-adjusted: 16.2% (15 mg), 17.7% (17.5 mg), 18.6% (20 mg), 17.0% (22.5 mg)
- In the pooled VK2735 groups, 90% of patients lost at least 10% of body weight and 32% lost at least 20%
- No plateau observed at week 21
"Placebo-adjusted" means the drug group's weight loss minus the placebo group's, which isolates the effect of the drug itself.
Maintenance (weeks 21 to 33)
The key metric is the share of week-21 weight loss still kept at week 33. Patients switched from VK2735 to placebo kept 61%.
| Regimen | n | % of weight loss maintained |
|---|---|---|
| Placebo | 27 | 61% |
| 17.5 mg QW to 5 mg QOW | 12 | 83% |
| 15 mg QW to 7.5 mg QOW | 13 | 90% |
| 17.5 mg QW to 10 mg QOW | 12 | 97% |
| Combined QOW | 37 | 90% |
| 17.5 mg QW to 10 mg QM | 16 | 82% |
| 17.5 mg QW to 15 mg QM | 14 | 84% |
| 17.5 mg QW to 17.5 mg QM | 11 | 90% |
| 20 mg QW to 20 mg QM | 14 | 86% |
| 22.5 mg QW to 22.5 mg QM | 10 | 85% |
| Combined QM | 65 | 85% |
All arms separated from placebo (p-values between <0.0001 and 0.004), with separation visible from about four weeks after the switch. The lowest monthly regimen (10 mg QM after 17.5 mg weekly) represents a dose reduction of roughly 85% versus continued weekly dosing.
Exploratory weekly control arm
Thirteen patients stayed on 17.5 mg weekly through week 33 and reached 21.7% weight loss from baseline (22% placebo-adjusted), still with no plateau.
Safety and tolerability
- During maintenance, rates of nausea, vomiting, diarrhea and constipation were not meaningfully different from placebo. All reported nausea in the maintenance phase was mild.
- One discontinuation due to an adverse event in the QOW arms and one in the QM arms
- Induction phase: one patient (1%) discontinued due to an adverse event, despite a faster two-week titration than the three-week steps used in the Phase 2 VENTURE study
- Note: Viking described induction-phase GI rates as similar to VENTURE but did not publish the induction-phase GI table in the release. That data is needed to properly judge tolerability under the faster titration.
Reading the data critically
- Exploratory, not primary. The study's stated objectives were safety, tolerability and pharmacokinetics (how the drug moves through the body). Weight change was an exploratory endpoint. The results are strong but should be read as supportive, not confirmatory.
- Small arms. Individual maintenance cohorts are 10 to 16 patients. The pooled QOW (n=37) and QM (n=65) numbers carry more weight than any single dose arm. The 97% figure comes from a 12-patient arm.
- Unbalanced induction. 118 of the induction patients were in the 17.5 mg cohort; the other dose cohorts had 14 to 15 patients each, versus 15 on placebo.
- One excluded patient. The 22.5 mg QM result excludes one patient whose result was more than 2.5 standard deviations from the cohort mean. Including that patient raises maintenance to 99%, so the exclusion makes the reported number more conservative, not less.
- Twelve weeks is short. We know weight loss is largely held for three months on less frequent dosing. We do not yet know the trajectory beyond that.
- Cross-trial comparisons. The 21.7% at 33 weeks in the weekly control arm compares favorably with tirzepatide's trajectory, but n=13, different populations and different trial designs make this hypothesis-generating only.
- KOL disclosure. The supportive quote from Dr. Louis Aronne in the release comes from a paid Viking consultant.
What this means for Phase 3
The Phase 3 VANQUISH program tests weekly subcutaneous VK2735 over a much longer horizon. This study does not replace that readout, but it reduces risk in two ways:
- Efficacy floor. A third independent dataset (after VENTURE and VENTURE-Oral) shows consistent, progressive weight loss without a plateau. The question for VANQUISH is no longer whether VK2735 works, but how far the curve goes and whether it can match or beat tirzepatide at 72 weeks.
- Tolerability. Low discontinuation under a faster titration is encouraging for real-world persistence, which is where many GLP-1 patients drop off.
The maintenance data also adds a commercial angle that VANQUISH alone would not give: a credible case for less frequent, lower-dose long-term therapy, which matters for adherence, cost of goods and payer conversations. Viking plans to test oral maintenance regimens in a part 2 of this study.
Financing
On September 23, Viking announced a $400M offering, upsized and priced on September 24 at $500M:
- 7,857,143 shares at $35.00 (16% below the prior close)
- $225M of 2.00% convertible senior notes due 2032, convertible at approximately $50.75 per share (a 45% premium to the offering price)
- Underwriters later exercised their options in full, bringing total net proceeds to approximately $547.8M (closed September 28)
Shares fell roughly 15% on the pricing day. Raising after a positive readout is standard practice and removes near-term funding risk through the Phase 3 program and the VK3019 amylin work, but it comes with roughly 9 million new shares and potential future dilution from the converts.
What to watch
- Full maintenance data presentation, including induction-phase GI breakdown
- Part 2 of the study (oral maintenance regimens)
- VANQUISH Phase 3 timelines
- Any partnering signals now that the balance sheet removes urgency## What happened
On September 22, Viking reported topline results from VK2735-102, a randomized, double-blind, placebo-controlled study in roughly 180 adults with obesity (BMI 30 or higher). VK2735 is Viking's dual GLP-1/GIP agonist: it mimics two gut hormones that reduce appetite and improve blood sugar control, the same mechanism class as Eli Lilly's tirzepatide (Zepbound).
The design had two parts. First, 21 weeks of weekly injections (induction), titrated up every two weeks to final doses of 15, 17.5, 20 or 22.5 mg. Then a 12-week maintenance phase in which patients were re-randomized to every-other-week (QOW) dosing, monthly (QM) dosing, continued weekly dosing, or placebo.
The stock rallied more than 26% on the day. Two days later, Viking priced an upsized $500M financing at a 16% discount to the prior close.
The data
Induction (weeks 0 to 21)
- Weight loss of approximately 16% to 19% across VK2735 cohorts vs. roughly 0% on placebo (p<0.0001 for all cohorts)
- Placebo-adjusted: 16.2% (15 mg), 17.7% (17.5 mg), 18.6% (20 mg), 17.0% (22.5 mg)
- In the pooled VK2735 groups, 90% of patients lost at least 10% of body weight and 32% lost at least 20%
- No plateau observed at week 21
"Placebo-adjusted" means the drug group's weight loss minus the placebo group's, which isolates the effect of the drug itself.
Maintenance (weeks 21 to 33)
The key metric is the share of week-21 weight loss still kept at week 33. Patients switched from VK2735 to placebo kept 61%.
| Regimen | n | % of weight loss maintained |
|---|---|---|
| Placebo | 27 | 61% |
| 17.5 mg QW to 5 mg QOW | 12 | 83% |
| 15 mg QW to 7.5 mg QOW | 13 | 90% |
| 17.5 mg QW to 10 mg QOW | 12 | 97% |
| Combined QOW | 37 | 90% |
| 17.5 mg QW to 10 mg QM | 16 | 82% |
| 17.5 mg QW to 15 mg QM | 14 | 84% |
| 17.5 mg QW to 17.5 mg QM | 11 | 90% |
| 20 mg QW to 20 mg QM | 14 | 86% |
| 22.5 mg QW to 22.5 mg QM | 10 | 85% |
| Combined QM | 65 | 85% |
All arms separated from placebo (p-values between <0.0001 and 0.004), with separation visible from about four weeks after the switch. The lowest monthly regimen (10 mg QM after 17.5 mg weekly) represents a dose reduction of roughly 85% versus continued weekly dosing.
Exploratory weekly control arm
Thirteen patients stayed on 17.5 mg weekly through week 33 and reached 21.7% weight loss from baseline (22% placebo-adjusted), still with no plateau.
Safety and tolerability
- During maintenance, rates of nausea, vomiting, diarrhea and constipation were not meaningfully different from placebo. All reported nausea in the maintenance phase was mild.
- One discontinuation due to an adverse event in the QOW arms and one in the QM arms
- Induction phase: one patient (1%) discontinued due to an adverse event, despite a faster two-week titration than the three-week steps used in the Phase 2 VENTURE study
- Note: Viking described induction-phase GI rates as similar to VENTURE but did not publish the induction-phase GI table in the release. That data is needed to properly judge tolerability under the faster titration.
Reading the data critically
- Exploratory, not primary. The study's stated objectives were safety, tolerability and pharmacokinetics (how the drug moves through the body). Weight change was an exploratory endpoint. The results are strong but should be read as supportive, not confirmatory.
- Small arms. Individual maintenance cohorts are 10 to 16 patients. The pooled QOW (n=37) and QM (n=65) numbers carry more weight than any single dose arm. The 97% figure comes from a 12-patient arm.
- Unbalanced induction. 118 of the induction patients were in the 17.5 mg cohort; the other dose cohorts had 14 to 15 patients each, versus 15 on placebo.
- One excluded patient. The 22.5 mg QM result excludes one patient whose result was more than 2.5 standard deviations from the cohort mean. Including that patient raises maintenance to 99%, so the exclusion makes the reported number more conservative, not less.
- Twelve weeks is short. We know weight loss is largely held for three months on less frequent dosing. We do not yet know the trajectory beyond that.
- Cross-trial comparisons. The 21.7% at 33 weeks in the weekly control arm compares favorably with tirzepatide's trajectory, but n=13, different populations and different trial designs make this hypothesis-generating only.
- KOL disclosure. The supportive quote from Dr. Louis Aronne in the release comes from a paid Viking consultant.
What this means for Phase 3
The Phase 3 VANQUISH program tests weekly subcutaneous VK2735 over a much longer horizon. This study does not replace that readout, but it reduces risk in two ways:
- Efficacy floor. A third independent dataset (after VENTURE and VENTURE-Oral) shows consistent, progressive weight loss without a plateau. The question for VANQUISH is no longer whether VK2735 works, but how far the curve goes and whether it can match or beat tirzepatide at 72 weeks.
- Tolerability. Low discontinuation under a faster titration is encouraging for real-world persistence, which is where many GLP-1 patients drop off.
The maintenance data also adds a commercial angle that VANQUISH alone would not give: a credible case for less frequent, lower-dose long-term therapy, which matters for adherence, cost of goods and payer conversations. Viking plans to test oral maintenance regimens in a part 2 of this study.
Financing
On September 23, Viking announced a $400M offering, upsized and priced on September 24 at $500M:
- 7,857,143 shares at $35.00 (16% below the prior close)
- $225M of 2.00% convertible senior notes due 2032, convertible at approximately $50.75 per share (a 45% premium to the offering price)
- Underwriters later exercised their options in full, bringing total net proceeds to approximately $547.8M (closed September 28)
Shares fell roughly 15% on the pricing day. Raising after a positive readout is standard practice and removes near-term funding risk through the Phase 3 program and the VK3019 amylin work, but it comes with roughly 9 million new shares and potential future dilution from the converts.
What to watch
- Full maintenance data presentation, including induction-phase GI breakdown
- Part 2 of the study (oral maintenance regimens)
- VANQUISH Phase 3 timelines
- Any partnering signals now that the balance sheet removes urgency